One simple but obvious feature they have is the ability to create DNS presets and apply those for new domains, it's really useful. (other people probably offer this)
Gandi also has fantastic support; it is slightly sad that they do not have a telephone number, but I get the vibe that Gandi is a real technology company and they believe they can offer premium support with support email. I agree, but I'd still like a telephone number for burning issues.
My only real complaint is that they have an unbelievably stupid login system where you log in not with a username, nor with an email address, but with an entirely random username. Mine is: PC5669-GANDI. It's infuriating if you ever need to use Gandi on a different computer. Why they saw it suitable to put their company name at the end of every login is puzzling.
Honestly though, its a minor criticism, and I love their "no bullshit" policy: http://www.gandi.net/no-bullshit
In my experience it is true.
I accidentally found out that you can actually cut out everything after and including the hyphen and it will still work.
This is not some crazy French law; Gandi has been in the registrar business for quite a long time and OVH loves standards :-)
Also, do they support DNSSEC? Ie, can I use their web interface to upload DS records to my domains parent zone?
The username thing is indeed very annoying though.
Here is the relevant text for NameCheap:
Namecheap may also cancel the registration of a domain name, after thirty (30) days, if that name is being used, as determined by Namecheap in its sole discretion, in association with spam or morally objectionable activities.
Morally objectionable activities will include, but not be limited to 1) activities designed to defame, embarrass, harm, abuse, threaten, slander or harass third parties; 2) activities prohibited by the laws of the United States and/or foreign territories in which you conduct business; 3) activities designed to encourage unlawful behavior by others, such as hate crimes, terrorism and child pornography; 4) activities that are tortious, vulgar, obscene, invasive of the privacy of a third party, racially, ethnically, or otherwise objectionable; activities designed to impersonate the identity of a third party; 5) and activities designed to harm or use unethically minors in any way.
The owner and publisher of this website is Gandi SAS, a simplified joint-stock company registered under French law with a capital of 37,000 Euros.
Registered with the Paris RCS – French Trade Registry - under number 423 093 459.
Intracommunal VAT number FR81423093459
63-65 boulevard Massena, Paris (75013), France
Gandi US Inc.
124 Lakefront Drive
Hunt Valley, MD 21030
> "For example, Gandi does not tolerate activity that is morally objectionable or that poses a threat to public order" 
From their domain registration terms:
> "Consequently, You commit Yourself to assuring that Our services are used in a licit manner and in conformity to Our Ethical standards" 
> "You commit Yourself to choosing and using Your domain name and Our services in a way that constantly respects the rights of third parties (intellectual property laws, personality rights, image rights, and the respect of private life, trademarks, etc.)"
From their general conditions of service:
> "By accepting Our Contracts and using Our services, You agree to abide to Our code of ethics which consists, in particular, of protecting and respecting minors, human dignity, public order and good moral standards, not infringing on the rights of third parties (private life, image, honor and reputation, trademarks, designs and models, copyrights, etc.) or the security of persons, property, the government, or the good working order of public institutions, and to help in the fight against abusive and/or deviant uses of the Internet (spamming, phishing, hacking, cracking, or attempts at hacking or cracking), or any other infraction as cited in the Penal Code." 
So Gandi reserves the right to revoke your domain name if it determines you violate one of their "good moral standards", or anyone makes any copyright claim against you. They essentially gave themselves contractual power to police the content of the sites on domains purchased through them.
So someone tell me, which registrar then actually has sensible terms & policies?
Though they only offer .org, .net, and .com and I believe the main form of payment is through paypal.
Nearly every provider has such a clause (including Nearlyfreespeech, Namecheap, and Gandi). I'd rather judge based on actions than on legalese.
You're right in wanting to judge by actions rather than some CYA phrasing in a terms & conditions. NFS has a track record of backing up that free speech mission with action. And then there's Dynadot, who continue to host the wikileaks.org domain, and the DNS after EasyDNS dropped them. If Gandi has a similar track record, I'd love to hear it.
Guess I'll just have to donate directly...
Revoked SSL based on trademark and Whois information.
Although the article does provide an update which says:
The reason for the certificate being revoked was because of the inaccurate whois data. Certificates really are a seal of trust, but that cannot be based on falsified whois data. It was right to revoke the certificate for this reason, but not without being in contact with the customer. We have reviewed and changed our processes to rectify this.
Mr. Marlinspike bought a SSL certificate from Gandi by giving them wrong personal information. When Gandi revoked the certificate, the support guys first wrongly communicated that it was probaly due to a trademark dispute, but it was actually just about the wrong whois information.
Ok, miscommunications happen, but what really irks me about Mr. Marlinspike is that he later went on to complain about how companies did not do enough to verify the whois information for SSL certificates. Which was, as we know, the reason why his SSL certificate was revoked.
What do we learn from this: Give correct whois information and your domain will be fine. For trademark disputes there is the UDRP process which not just Gandi but also most other registrars (including namecheap) have agreed to.
I couldn't find it easily, but are there better prices for transfers?
I recently asked them why they charge more than competitors for, this was the response:
Thank you for contacting Gandi Customer Care. It is true, Gandi does charge slightly more for
domains than some other registrars. We do feel that we are still affordable, however. The
reason we need to charge a small premium is that we have a different business model than
other, larger companies, and cannot get by on razor-thin margins. We are a commercial
organization, certainly, and we do make money, but we also support the community of
innovators in the hosting and domain name management space, and we do not advertise, but
rely on word of mouth for our marketing. We do not buy market share with ads, and we do
not make empty promises to capture customers.
We also include some services (such as a free year of SSL certificates and the ability to
obfuscate your whois data) that other registrars tend to charge incrementally for. This is
because we believe that your data is yours. We will never sell your private information as
some others do, and so we do not have that revenue stream.
We appreciate your willingness to consider Gandi as an ethical, no-bullshit alternative to
GoDaddy. Right now a lot of domains are available at $8/yr through the end of 2011. We
hope you will join us.
Does Gandi offer something that others don't?
As for the amount, I'll admit that it isn't a great deal, but while $5 won't break me, it's a matter of scale. I've been transitioning from GoDaddy for awhile now, but at the moment, I still have about 20 domains hosted with them.
20 x $5 is $100, which means I can be free of GoDaddy for $x with Name.com, for $x + 100 with Gandi. Again, why would I pay more when there are known good options for less?
I'm pretty sure the right way to go about it is to move DNS first, but it seems Gandi does not support this (unlike Namecheap).
My DNS is hosted with the current registrar which, shall we say, is not terribly pleased with people leaving. So I would not put it past them to cut off my DNS service.
Same reason I recently switched to NameCheap during the whole 'GoDaddy supports SOPA' affair.
Gandi.net headquarters is based out of Paris, France (although they do have a US office).
One thing to bear in mind.
Gandi.net does not offer full whois privacy by the way, so your name will always be revealed.
After that I switched to slicehost who's equivalent VM performs even better however I don't think you can sign up for that anymore now they've been assimilated by Rackspace.
Didn't have any unscheduled downtime over 6 months on Gandi.
The third word on their site is an expletive. This made it too difficult to justify in a Powerpoint presentation.