I would upgrade a little bit and buy part of the system now, and then the other half later. Here's what I would buy if I were you:
-2 MTS-01 Towers (on sale $1199)
-1 MCS-01 Center (on sale $479)
-and the receiver of you choice
THEN when you can afford it....
-wait for the M-series Bipole surround speakers to come out (definitely coming out there year)
-and a really nice subwoofer or two (maybe the PB13- Ultra)
*Remember SVS will hook you up when buy multiple products from them. In this economy its not usual to get better deals than advertised
Now you have an awesome system that will HOPEFULLY keep you satisfied for a while. When you get the 2nd part of your system, PREPARE TO BE SHOCKED!!!!
-Pete