Has anybody been converting wav files to WMA using WMP? If so, do you hear a noticable difference between WMA and MP3 files at the same conversion rate?

It's rather well accepted that WMA files have better fidelity than MP3's at the same bit rate. At 128kbps, most average schmoes can hear the difference. Beyond that, I think it takes a machine or a golden ear audiophile to tell the difference.