Slipped my mind that you went to Github. Definitely looks a lot like Bootstrap as well. Though if it wasn't inspired by Dropbox, there are nevertheless some strong similarities. Namely the signup form, footer and the call to action for the paid product. I can see developers not understanding what I mean, but surely a designer must!

Not trying to be critical by the way. I'm a huge fan of every company/framework/person etc mentioned here. I'm just really interested in the form, function and messaging of homepages.