I specifically object to the idea of categorisation by instruments.
There's a category for piano. I am a pianist, but I find the concentration on the piano slightly disconcerting. Then orchestra and a pop/band/jazz/everything-else. Basically, anything that isn't piano or orchestra goes to the third category, including chamber music, music for solo instruments other than piano, opera, electronic music, and so on. This renders those categories virtually useless.
Categories have been installed, disliked and subsequently removed twice already. I thought you should have realized that by now.
EDIT: Eek. Now a category for experimental and atonal music. What the? What about atonal orchestral pieces, where do they go?
EDIT 2: I also see that string quartets and brass quintets have been put into the orchestral category. I recommend that you go to the library, grab the New Grove and look up the definition of "orchestra". Also, what about the "orchestral arrangements" in the description? I have a few orchestral pieces, and they're most definitely not arrangements.