I'm at the Conversational Marketing Summit, listening to a chat between organizer John Battelle and Intuit founder Scott Cook. Batelle is asking about Intuit's online presence. Cook says he'd move all his business online in a heartbeat if he could, but that many QuickBooks business customers don't want to run their accounts online. And not for reliability or accessibility reasons.
Rather, Cook says, his customers want to know where their data is at all times, since in many cases, they're keeping somewhat fictional accounts for their tax reports. Should the IRS come knocking, Cook says, "Format C:..."
You can't do that on a Web drive. Something to keep in mind if you're building a Web service for business.