Google's weakness in the enterprise productivity software market segment is that they have no track record of providing stability via long term backward compatibility and support for obsolescent software - e.g. the Chrome Browser. Furthermore, the enterprise market is not a significant piece of the core strategy - it just doesn't grow fast enough and it requires the dedication of a highly trained salesforce and a commitment to long term support of each software release.
IBM can compete with Microsoft on the same basis as they have for the past twenty years - as an ecosystem.
Google's paid cloud app stuff didn't even have urgent telephone support until recently, and there's still not (and not going to be, I think) any way to get your google rep to explain stuff to you over the course of a few months (and fancy dinners out), before finally tailoring you a customized (and pricy) contract.
Microsoft, I think, knows how to do those things much better than Google, but are instead hampered by the relatively pukey quality of their cloudy offerings so far -- they're playing catch up, years behind Google, and internally conflicted by the still-huge revenues of their legacy cash cows.
I'm not saying IBM can win in this market, just saying that Google Docs, Dropbox, Evernote, and all these cloudtastic superheroes of the consumer market have yet to achieve significance in the weird altiverse of Big Corporate.
Now it's a for profit venture out of the gate, no free use for ad impressions or anything like that, but I could see them bringing some novel concepts to the table. That's assuming they are serious about it. Integration with other enterprise apps and enterprise cloud apps, in a single app suite with the best uptime and reliability around. It's not super sexy but I could see a market for it if they're serious.