Vendors will tell you that most of the CMS action is now in the mid-market -- that is, point web content management (WCM) solutions where product licensing starts at $40-80,000 USD.
...Looks like FatWire. After a marathon bidding session for poor divine's assets, auction attendees are reporting that FatWire will come away with Content Server.
Should major CMS software vendors also provide their solution as a hosted service? None of them do right now (though some of their partners have set up ASPs).