This is the right move. Great brands have a logo that can be reduced to one color, not only for faxing (as the blog post mentions) but for embossing, stationery, signage, and many applications that would be overly costly when printed in multiple colors.
The change happens to coincide with the "flat" trend, but I see it as a necessary evolution for a brand that has grown into the mainstream and requires consistency across different media.
Of course the logo itself leaves something to be desired, from the genericness of the concept to the strange and inconsistent perspective of the flaps. But remember, it's not just a logo, it's also an icon that sits in your dock or toolbar. As a software company it makes sense for Dropbox to have a logo that can also be a functional and iconic UI element -- another reason why 1-color makes sense.
Dropbox much like Google acquired its customers through utility, not by having a great logo. It will be a hard fought battle to make "the box" symbol synonymous with Dropbox, but if they can own it, it's certainly a powerful mnemonic.
Simplicity can be the outcome of good design, not necessarily always a sensible goal in of itself. The right thing might be complex, or it might be simple. The simpler it is, the less room there is for error, and in this case I feel like the outcome is an ugly icon. Obviously the flaps for the box are visually "off" by design, but why? It's not for me at all.
I personally don't like this flat take on logos lately. It seems like designers are taking the easy way out. No shades, no shadows, no depth. It's just a 2d logo. I like the new Firefox log thought, it's flatter but not all the way flat-looking.
The icon still needs the words "dropbox" which was dropped.
As a brand they are not "nike" or "apple" or an automobile. That aren't that famous yet. And the logo isn't that memorable.
Seeing that logo (w/o the words) has one effect on knowledgeable users and another effect on newbies and people to whom dropbox means very little as a company (people outside of startups).
As an aside the logo (imho of course) isn't that good and makes your eyes go in different directions. It really could benefit from the words appearing in proximity.
Above opinion based on my many years in the graphics business and observation of business and branding over time.
The change happens to coincide with the "flat" trend, but I see it as a necessary evolution for a brand that has grown into the mainstream and requires consistency across different media.
Of course the logo itself leaves something to be desired, from the genericness of the concept to the strange and inconsistent perspective of the flaps. But remember, it's not just a logo, it's also an icon that sits in your dock or toolbar. As a software company it makes sense for Dropbox to have a logo that can also be a functional and iconic UI element -- another reason why 1-color makes sense.
Dropbox much like Google acquired its customers through utility, not by having a great logo. It will be a hard fought battle to make "the box" symbol synonymous with Dropbox, but if they can own it, it's certainly a powerful mnemonic.