I've yet to find a naming scheme that is flexible enough for every situation.
Anyway as of today my standard for pop, rock, jazz, etc. is the following one:
Artist\Album\Track - Title.Format
Ozric Tentacles\Become the Other\05 - Neurochasm.mp3
or
Various Artists\Album\Track - (Artist) Title.Format
Various artists\Natural Born Killers [Original Soundtrack]\15 - (Nine Inch Nails) Something I Can Never Have.mp3
Things gets a lot more complicated for classical music, where I want to have at hand also information about the conductor and performer(s) or orchestra and very often also about the movement and tempo.
Some examples:
Johann Sebastian Bach\Brandenburg Concertos, Suites No. 2 & 3 - Concentus Musicus Wien - N. Harnoncourt (Disc 1)\01 - Brandenburg Concerto No. 2, BWV1047 - 1. Allegro.mp3
Wolfgang Amadeus Mozart\Die Zauberflöte - Berliner Philharmoniker - Herbert Von Karajan (Disc 1)\02 - Die Zauberflöte - A1 Nr. 1 - Introduktion- Zu Hilfe! Zu Hilfe!.mp3
Various Artists\Arturo Benedetti Michelangeli Live (Aula Nervi, Città del Vaticano, 13 giugno 1987)\01 - Ludwig van Beethoven - op.2 n.3 - 1) Allegro con brio.mp3
In this cases to pretend to store also artist and album name in the filename it is obviously infeasible.
I must add that all the information is also stored in tags so I can easly batch-rename my files the day I change may mind on my naming scheme (which already happened a couple of times).
Right now I'm considering that the lack of "year of release" information is a major drawback and I'm considering to include it in the "album directory" name. That will not anyway will be a match for compilation of material released in different years.
One more thing: I also use mp3collector from collectorz.com to organize my library. I find it almost perfect, letting me to search for every field and look at my collection in inifinite different virtual views, with only a MAJOR limit: like the name implies it is only for mp3. (Anybody listening from collectorz.com???)
I've yet to thoroughly test if the new Winamp 5 library fits my needs, but the first feeling is it will not. Same for iTunes, which anyway i'm reluctant to adopt as I'm a Winamp addict.
Sergio