I currently have 12,400 songs in my iTunes (just over 100gig) and about 1000 of those are audio book tracks - so we'll say 11,000 song titles.
I have systematically gone through most all of my songs and RATED them. I think rating songs and placing them all in appropriate genres is the key to long term music library enjoyment.
Here are a few of the things that I do to process through the vast library challenge:
Create a playlist (assuming you have the ability in your library management system) that has a GENRE of your choice and has NO RATING. Then, on a roadtrip or long commute or wainting in an airport, etc - process through the unrated playlist. You don't have to listen to the whole song, you'll know fairly quickly if you like the song or not.
Here is my rating process: (remembering that this is done all within the genre. i.e. - my CLASSIC ROCK genre has it's favs and those are probably more desirable than my favs in the DANCE genre.)
1 STAR: there is something wrong with the song - bad rip, poor quality, etc
2 STAR: could care less if I hear this song again, I would not choose to find and listen to this sing on any given day
3 STAR: don't mind the song, pretty good and probably would not skip it if it popped into my playlist rotation
4 STAR: this is one of the tops, will often seek it out and play it and look forward to it popping into my playlist
5 STAR: all time favorite! Will (under normal circumstances) never balk at this song playing.
These steps are critical if you really want to hear more than the top 50-100 songs in your library. Then, you can use your simple logic statements (within iTunes) to create some great playlists.
Good luck!
Sproles