Which businesses do you think are making this shift? I work in the enterprise space doing desktop transformations, and never once has anyone even requested something like Google Docs. It's a myth. Google is trying to leverage their web search "platform" to increase the share of the desktop, but it's just not a logical link.
Microsoft may find some success with Office 2010 web edition, but only because it complements an already very successful thick client.
So whilst web apps have a future, it won't be this year, or next.
Damo
I agree with you that no company would use Google Docs just because of security concerns. The people who actually use Google Docs as their main office tool is less than 1%. But I also think that there is opportunity in this space for someone to step in just like Blackberry did with PocketPC. If there is a web app that could have a lightweight thin client and alleviate worries over security, it would be a success.