So here's the good news: Turtle Beach announced a universal version of their gaming-oriented chat headset. In stereo, it mixes your talking with your gaming perfectly, meaning you won't be shouting at your teammates (unintentionally). Here's the bad news:
Just like the otherwise superb Astro A40s, the Ear Force PX21s require a lot of cordage - namely, a USB plug for chat audio and a line to your stereo RCA outputs. Plus, they cost $US80, which, at $US20 more than Turtle Beach's similar Xbox 360 exclusive stereo headset, is putting you into surround-sound headset territory.
But if you game a lot on the 360 and the PS3 - which many of you do - the PX21 may be worth a look.