i had a rebel xti for a while, i didnt really read the whole thread, but ill trow in my 2cents real quick
shoot in raw, you will be able to edit it very well
learn how to do hdr (i was thought but a photographer friend), hdr is when u take 3 shots of the same "picture" one thats dark one thats perfect and one thats very bright
the hdr software that you will use will put them all together and give you a great picture at the end. it will avoid you having to photoshop the imagine and you will get great looking quality shots. (will take a bit of practice)
also you will need a 10-20 lens !
im picking up a t1i in the following weeks, still doing my homework on my final decision (i shoot videos also of the house) and im still a little unsure between the canon or the d5000 and d90 by nikon !
good luck and enjoy !!!!!!