Live view doesn't really appeal to me, but Canon's noise-reduction capability does. I'd have to see how the 40D does at high ISO before I even consider switching.
Then again, in-body SR might keep me in the Pentax fold for a long time. I checked prices for IS lenses over at B&H earlier, just to see if I could afford a switch. I just can't, and SR really does a lot for me.
I would understand professionals or people with specific needs wanting to switch, though. Fast long lenses really are Pentax's weakness, as well as lens availability and choices in general. One look at all the lenses available to Canon or Nikon systems can really give some second thoughts about switching.
Agreed with previous posts about the body not mattering much if you don't have the glass to go with it. I think the K10D can hold it's own at least for the next few months, especially with price reductions and rebates. What Pentax really needs to announce are new lenses. Heck, even an announcement of the re-issuing of FA* lenses would be much welcomed by Pentax users.