I think all of the answers above are good ones. I, for one, am very glad they did weather seal it. It was pretty darn nice for me to spend only $800 on a DSLR kit and get a weather sealed body. I can't tell you how many times taking my previous *ist DL into snowy conditions (that happens alot here in West Michigan
) freaked me out! I even recall having an argument with my wife due to her wanting to take photos of the kids going down a sledding hill during some wet snowfall....
True, non of my lenses are weather sealed, but if it becomes that important, I can upgrade my lens. If not, I throw on the kit lens and hold it face down when not taking the shot. As already mentioned, brushing a couple of drops of water off the outside of a lens is much easier than dealing with water drops that fall onto buttons for sure.
off topic: due to this thread, I just disovered that the new kit lens cost twice as much as the older version. Looks like I'll be more careful than I thought.