That's not really a great difference though. Couple years time and Larry will be doing other things or working on some newer, more interesting problems. I don't see this API surviving more than a couple years considering the speed that Google Docs/Drive continues to change.
The difference is Drive is a flagship "L-team" product, so it's pretty much on equal standing to Google+ in terms of priority. When Larry Page took the helm he created 7 core focus areas + accompanying SVP's (A nice summary: http://tech.fortune.cnn.com/2013/01/03/google-larry-page/).
Last weeks reshuffle which had the Maps and Commerce units absorbed into the Knowledge and Ads units respectively and Pichai taking over Android brings it down to 5 focus areas:
SVP of Knowledge/Search — Alan Eustace, SVP of Identity/Social — Vic Gundotra, SVP of Advertising and Commerce — Susan Wojcicki, SVP of YouTube/Video — Salar Kamangar, SVP of Android, Chrome and Google Apps — Sundar Pichai
The key distinction between Drive and Reader is that Drive is pretty much the embodiment of Google Apps itself, whereas Reader was an orphaned product which didn't have a home in any of these 5 post-Page areas.
Any change to this API in a couple of years will be the introduction of v2.
Drive is now a pillar of Google's services, not just Apps but Google Now and search rely on data stored in it, and with many competing storage services around any differentiating feature is worth having.
