You know this is a very interesting question and one that i've been doing a little experimenting on.
Syntrus I would ask you to go to my MaestroSegments account, on that account I have uploaded 3 loops, 3 simple, small loops, with a LOT of keywords attached to the piece describing it's nature.
Out of 3, 2 of them have been used already.
I tell you the only reason our songs arn't being spit into every project is the fact we as audio artists never use descriptive words for our pieces. It's always "LOLZ, I WUZ X-PERMIMNTERING!"
and of course no flash artist looks for that.
But if you write
"A sad piece with alot of hopeful ambiance"
you have
sad (searched for a lot)
hopeful
ambiance
those three keywords act as nets to flash artists.
The fact that two of the three loops I uploaded there being used is proof.