Me and some friends did a little test
we ripped a chart cd one time in ogg and mp3.
first with 192K & 128K then lower ( think i t was 64K and another i don't remember)
And one time pure WAV -
so to make it short => OGG sounds very much better than MP3 on lower bitrates. On 128K and higher bitrates we couldn't make the difference - so when you use lower bitrates I would opt for the fish (OGG) but if you want 128 standart you can use both.
Sometimes we even couldn't recognize the wav file !
I think that MP3 will be the standart for some more time (because most people don't even know OGG!)
but OGG will grow fast and one day you'll see more OGG than mp3 files on your P2P proggy.
Did I tell that Prof Brandenburg - the head of Frauenhofer's MP3 Project is at my University - in 2 weeks i'll have him as professor
So for those who followed know you know where I study