I'm considering migrating to OGG Vorbis and FLAC (two open and free music formats) because:
-Well, why the heck not? I've got the hard drive space.
-Because it will force me to remember which albums I truly loved and need to keep, and archiving or deleting the rest
-Because FLAC will let me re-encode my music for different devices (say, MP3 for the iPod, or OGG if I buy a Cowon or such)
-Open formats, open standards, etc.
I wish I had a good used CD store nearby. I guess Amazon will have to do.
My current music library is 7.8 GB and is made up of mostly high bitrate MP3 files. (This doesn't count the podcasts, which add up to about 3 GB). The large majority of this music was downloaded from Amazon MP3, eMusic or Lala (back when they existed), though some I ripped and tagged myself. A small slice is from Jamendo or similar sites. It's all legal, though, which as far as I can tell is a rarity in my age bracket.