There were 6 things that made me choose the K200d as my camera.
In reading the reviews, three little bits of information popped up
1) the Canon 40d (which I was also considering) gave "soft" photos.
2) the XSI's resolution put the Canon 40d's to shame
3) the Raw test showed that while the XSI displayed slightly better detail in RAW due to it's two extra megapixels than the K200d, they were essentially the same
Those are the words of the reviewers. They aren't mine. But they were there, and I read them, and putting two and two together, I came up with the K200d as having the ability to take great pics on par with the 12 MP Canon XSI and better than the 40D. That may or may not be fact, but it is how I saw it after spending countless hours trying to come to a decision. And again, it was just the conclusion I came to, and I have nothing other than the reviews to back that up.
4) One forum had a number of very heated debates about in lens or in body stabilization. And while the consensus on that forum was that in lens was better, the majority of them were shooting with non stabilized lenses because they could not afford the IS lenses. Even if SR only gave one or two stops vs the 3 or 4 of a stabilized lens, the IS in the lens was pointless if you can't afford the lens to begin with. I'm not a pro. I've got a wife, kids, mortgage and car payments like a lot of folks. Something is always better than nothing. Well, usually anyway
5) focus issues with the XSI. They are out there, and if you read, there are post all over the web about it. Some of it is attributed to being new to DSLRs but one review site even noted it in their review.
6) Build Quality. Even compared to the 40d, the Pentax camera line seems very solid. The lenses all have metal where they seat, not plastic. I dont know if that makes a huge difference, but it is just a small detail that points to the care with which these cameras are made. Holding an XSI and a K200d in your hand is night and day. It is pretty obvious that one is made for the consumer market with mass sales in mind.
Just so you don't think I am anti Canon, I was looking very hard at the K20d also. In my mind, there were just too many post about things with that camera that made me shy away from it. Being a brand new sensor, it might be that some of these issues are real and need to be worked out. I also own a Canon S5IS and it is a wonderful and fun camera that takes great pictures and I am glad I bought it and will continue to use it.
If live view is important to you, and you see yourself shooting a lot of pictures very fast, then maybe the K200d is not for you. Those things were not that important to me, so I choose the K200d. If the XSI would have had the same build quality as the K200d, it might have been a different story, or at least I would still be thinking on it instead of learning my new camera.
Al