We want Dropbox to be the home for all your stuff, and we think this beats using two different services or having to log out and switch accounts. More importantly, this is a huge step toward making Dropbox even better for work, and we’re excited to share everything else we’re cooking up. We’re rolling this out to Dropbox for Business customers starting this month — check out our Dropbox at work to learn more.
This is definitely a needed feature. The link also shows a picture of what I assume is the Dropbox for iOS 7 update. If you check out the 2nd link, you'll get an idea of what multiple accounts will look like on the Mac.