I would echo an earlier post on spend more on speakers than the receiver...
To make my point, I am still using the same 5 primary speakers I bought in 1996, but I'm on my 4th receiver (and I am a slow upgrader), third projector, and 5th (or maybe 6th) video source. The tech in receivers changes and you will want (or need) to upgrade later. However, speaker tech is pretty solid and if you buy correctly now, you may never need to buy speakers again.