I am usually a big researcher before I make a big purchase. I read articles, blog posts, forum discussions and anything else that I can find where people discuss their purchases.
One of the things I hate is when all this research reaches critical mass in my brain and it just becomes a never ending merry-go-round of details. Every few minutes I sway one way or the other. There is a point in the process where I seriously can not make a decision and it pains me to go one way or the other. That's where I am now. Eventually the merry-go-round slows down and focuses on just one answer. And after all of this I always feel good about my choice because of the process I went through.
So my current merry-go-round? Which camera to buy with my refund. I had pretty much decided to get a 40D, but I'm getting a little more money than I first thought so now the 50D has popped into the equation. With the 40D I could get the camera, a wide angle lens and a new tripod. With the 50D I could get the camera and a wide angle lens. This may seems like an obvious choice (get the one where you get more stuff), but I will have this camera a VERY long time. As a poor teacher I can't swap cameras out every two years like most photographers seem to do. It will probably be with me at least three to four years (my XT is four years old). When you factor that into the equation it seems like I should take the one with the newer advances. Back on the merry-go-round. Round and around we go.