What I've noticed is that, unlike MP3s, OGG/MPC files don't buckle or start showing artifacts when passed through effects processors which is nice when working with prepared samples in audio/music production (and where, of course, lossy compression is acceptable).
OGG/MPC is, in general, better than MP3 both on the ears (more expansive sound stage, better high frequency support, etc.) and in general utility. Most anyone with a good ear will tell you the same thing. I like MPC over OGG because MPC files tend to be smaller than OGG files at similar quality levels.
Ultimately, this is a very subjective topic and all the arguing is unnecessary, egoistic, and inflammatory. When ripping, I usually rip an MPC version for my online archives and an MP3 version immediately backed up to CD to be used in portable devices or my in-dash MP3 player.
Your mileage may, of course, vary dangerously.