Hello!
I just purchased a 4100NEX (upgrading from JVC NT800HDT). My iPod has a ton of songs, a lot of which are compilation albums such as soundtracks, greatest hits, etc. I set them as compilation albums so that my artists list isn't flooded with artists that only have one or two songs.
On my JVC, and on the iPod directly, I could go to Genre->Soundtracks->All Albums and see all my soundtracks.
On the Pioneer, Genre->Soundtracks is empty. I noticed this for all albums that are compilations. Genre search in general is working as long as the album/song isn't in a compilatio