I thik you talking about GMail drive that provide space to save your document your gmail account and accessible everywhere when logged in gmail account.
Similar to DROP Box or iCloud service from Apple, its a cloud storage service, where you can store any data and retrieve it anytime, anywhere. Google offers 5 GB free storage, and for more you gotta pay!
It's just Google's answer to dropbox. I expect to see heavy integration with Android and such in the future.
Drop box came before google drive, what are the shortcomings that google is trying to overcome with this launch?
what and how does application program interface difference applies to google drive, sugar sync, cloudi and drop box?
how does google regulates the release of newer applications? it is chronological or based on the country it targets?