It's unclear to me reading the SES docs how their spam handling will be; what they will be doing to police those with whom I share an IP address; and many other things. However, what is clear is that at no point will anybody respond to my support request at 11pm as your staff did the other night.
For me personally:
SendGrid is completely transparent to my application since it's just an SMTP server.
SES is a web services API, so I need to either (a) rewrite my app to take advantage of it, or (b) write my own SMTP wrapper. Either way, it's code, and I can't imagine ever writing code to save a few dozen dollars per month.
If Amazon offered an SMTP server like SendGrid does, then I could imagine switching, but until then, the monthly savings are negligible.
For new apps it's an easier decision.
mta's have been doing asynchronous message queuing loooooong before it was cool with web developers.
*note, the ones who go off on a tangent about mta holy war's are the bad ones
Also the free Sendgrid addon for Heroku is a dream for throwaway apps.
My time is quite valuable, and the costs of Sendgrid aren't even a drop in the bucket compared to other costs. So I don't plan on switching any time soon.
Don't they charge separately for every application? I found myself not using the Heroku add-on so I could combine all my sending into one account.
We were looking around for an email service early this month; Amazon SES seems like the reasonable choice for us; hard to beat.
From what we have learned, Amazon SES does little more than send out emails. If you have the resources to implement your own list management, campaign management, DKIM signing, reporting, etc., then it's a great choice. If you need a company to do this for you though, you'll still want to go with a service like JangoSMTP.
I work for JangoSMTP and we get a lot of clients coming to us from other transactional email providers because they need more. Deliverability is a major issue that comes up. You may be able to send out mass quantites of email, but without an experienced email marketing provider you may struggle to reach people's inboxes. Delivery is as much an art as it is a science, and it takes constant focus to stay on top.
Also, Amazon only offers an API. JangoSMTP gives you the option to send through an SMTP server as well as API. We also offer open and click tracking, as well as advanced reporting (Google Analytics, logging, etc.). If reporting is important to you, you will want to consider a service like JangoSMTP that is more advanced than Amazon SES.
-useful comment on the blog page, and missing from HN comments
On the other hand, if their "in-house content filtering technologies" prove effective at stopping spammers, how many legitimate users will get banned as false-positives?
How much would you really save, assuming for your use case that Amazon is a lot cheaper, by waiting for 90 days? After all, you have to re-write and test your code to use the SES API anyways (maybe; or you can use their special script).
The other thing to consider is deliverability from Amazon. I would hope that they run on a different IP range than EC2, but besides that they have a different risk profile than other SMTP hosts. Amazon is able to make it as cheap as they do because their risk is based on implementing quotas based on reputation in addition to making you verify the sender address (both making it quite difficult to use the service to send spam).
So far that makes it pretty solid. The only thing I haven't been able to figure out so far is how to set DKIM keys.
Regarding the scale, the company I work for sends more mail per month than the x-axis shows, so not so preposterous.