So the Amazon Cloud Player will play music I’ve uploaded to the Cloud Drive, not just newly-purchased Amazon MP3s. That’s nice.
And Amazon’s add-on storage prices are much better than Dropbox. Upping your account to 50GB will cost you $50/year on Amazon, as opposed than Dropbox’s $9.99/month or $99/year. Upping the plan to 100GB will cost you $100/year on Amazon, double that on Dropbox. And Amazon has more storage capacity options than Dropbox.
Sure, Amazon gives you more free storage out of the gate (5GB vs. 2GB), but by jumping through a few simple hoops I’ve already achieved 4.25GB in free Dropbox storage, so that’s almost a wash.
All that said, the lack of an OSX, Windows or Linux native application for seamlessly synchronizing files with your desktop (not to mention an iOS app for data retrieval) makes the free version of Dropbox still more useful to me on a day to day basis than Amazon’s Cloud Drive.
(So, um, Apple… where’s your cloud storage product? Hmm?)