Most significant line: "Unlike Dropbox, ...Google Docs' storage offerings are a bit more complex."
The beauty of Dropbox is its simplicity and seamless integration. Sounds like GDrive is more iCloud than Dropbox, so I'm not sure how accurate the term "Dropbox-rival" really is.
Dropbox is fabulous product, easy to use and does its job very well. Not to sure if GDrive is going to be competition to it, unless and until GDrive tightly integrates with GMail, the must use offering from Google (other then Search).