My wife bought me a lovely new set of Sennheiser HD-555 headphones as a birthday present. I don't really listen to music but I do have an engineer's understanding of muddiness and distortion and it is lovely to have a set of headphones which reproduces the sounds in game as they are supposed to be. I briefly considered asking her to get me a set of surround sound headphones but reading comments from serious audiophiles convinced me that the trade-off in quality is not worth it. The clincher for me was the realisation that we only have two ears which means that with proper down-mixing it should be possible to perfectly emulate surround sound with just stereo headphones. Creative's CMSS technology aims to do just that and I can happily verify that it is still very good and does give a feeling of depth in the aural landscape of a game while allowing you to pinpoint sound sources in the horizontal plane (but not up and down sadly).
The headphones do lack a microphone. This isn't an issue at present as I am in an unsociable single player gaming phase but I will need to get some kind of stand alone microphone (a lapel micro-phone perhaps) eventually.