I agree with you that Google is moving into an area Microsoft used to be in with IBM, but I feel like Google, while it does nice things like this, is similarly going to the same location. There's nothing stopping from other companies from coming up with something similar; the problem for now is adoption.

I'd like to find a document editor outside of the major competitors like Microsoft and Google, but to be honest, the others are frankly terrible by comparison. When that changes, at least in the document area, Google is going to rethink what they're doing or buy them out (which is also possible).

The one thing that ties all of these services together for now is Gmail. Because it serves as a single login, it makes transition to other Google owned products easier. Besides being good at the services they provide, this is the real grease in the wheels that makes the whole machine run.

We're already seeing other services crop up to fill the niche YouTube is filling. Vimeo, for example, is actually quite good. While it doesn't have a lot of the silly videos and stupid clips YouTube is famous for, it's got a lot of creative people making beautiful content. But tying Vimeo to a document editing platform?

We're not quite there yet.