Upgrading 2nd Home Theater - Should I go 7.1?

[DFWHD]

A couple of years ago when we bought our home, we dropped about $8K put in a decent 5.1 home theater setup in our main family room (52" LCD, AVR, Blu-Ray & speakers). At that time I took my old 5.1 gear and put it upstairs in the game room for the kids. Since then, I've slowly upgraded the game room TV to a 61" DLP and then upgraded the receiver to a Pioneer VSX-92TXH AV receiver capable of 7.1 surround since that room now had the bigger screen. Now it is time to upgrade the old speakers and I'm trying to decide if Blu-Ray has enough 7.1 offerings to justify adding the 2 additional speakers. I'm trying to do this under the radar since we just did the family room theater in 2007, so if I can save the cost of the two additional speakers for now, I'd like to. I'm also wondering if I'd notice the difference since in sound since the room is only 12 x 15. I appreciate any feedback.