I just tend to think that the optimal cloud solution is as close to invisible as possible while letting people use whichever software tools they need. I don't really see any single entity owning the software and the storage because no single entity can own the collaboration tools. I view collaboration and syncing as two distinct business lines without a whole lot of interdependence. Personally I use Google docs once in a blue moon, and even when I do, I don't see how Google Drive makes that process any easier.
It may be that I just don't understand the product, but I don't think this will be any more successful than its competitors except for the fact that, when compared to Dropbox, it is substantially cheaper. But then again, Dropbox may be able to parter with Amazon to keep Google out of the space as much as possible and keep costs down.
For me, the fundamental problem with a service like Google Docs is that it is the ONLY way I can edit a document.
Whereas on my computer, I can open a .doc file (synced with Dropbox) in Word, TextEdit, OpenOffice, NeoOffice, or just about any other document editor. Doubly so for more platform-agnostic files (e.g. txt, jpg, pdf, etc).
(This is also why, unlike Steve Jobs, I hope files and the file system never die.)
The biggest problem with the file-based route is when you have multiple people working on one file. You can't work on it at the same time (or you have a merge problem.) You have to sidechannel quite a bit about which version is the current "master". All kinds of issues that are solved by using a non-file-centric document.
Syncing solutions should not dictate which software you use. One environment should be completely agnostic of others and only be tied together by file formats. So my original point was that I don't see the value add in Google Drive overtaking Dropbox just because it has accompanying productivity software. I think the software has to stand on its own, which I do not believe it can do.
Easier to explain via my own example: I have Dropbox, and I'm also a fairly heavy docs user. Now that's there's Drive, it's a no-brainer to just take all my files out of Dropbox and drop them into Drive so when I'm looking for something like a letter from last year, I only have to search one web site / app and it's got everything from docs to PDF scans. There's no comparable way of going the other direction (moving all my files to Dropbox) without losing a ton of functionality. Word is good, but it's really primitive compared to Doc at this point when it comes to collaborative work and access on my phone, tablet, etc.
It's also worth noting that in the case of Google Docs, Drive isn't really a syncing solution (unless you're using Docs in offline mode) since there's no files to sync. It's just a way to access your docs.