I've just noticed that there is a new Microsoft service available on the web: Office Live. and I tough that it was worth at least a look, so I tried to enter it using my MSN account and this is what I've reached ;)
It seems that it has a many limitations to the combination of browser and O.S. it is compatible with, first under linux it just doesn't work, second no support for Opera and Chrome.
So it has a long way before being competitive with google documents, at least from my point of view ;).
This is not uncommon for Microsoft, mac user do know how the support of MSN lack from their side, but this is Microsoft way of doing.
Well I think that I continue using OpenOffice and Google docs ;)