i am with chris on this one... 2 extra mp! bah! what are you going to do? print posters? how many people actually print poster size prints here? not many if any. i have taken 1100 or so pictures with my new camera (d40) and havent printed a single one...
the only advantage i can see for the extra 2 mp (if kyou arent printing) is that you have a bigger picture to crop from... if you crop your pictures.
most of us take pictures for the web so the 2mp is for the most part irrelevant IMO.
will the 400d take good pictures? well it can but its really the users skill that takes the pictures.
ps: dont disregard nikons. they have great chips and software for picture taking too