Hospital usually put out about 2 or so compilations throughout the year that cover more or less the whole scene.
RAM Records usually put out a compilation at the end of the year filled with their most popular tracks.
Just check out most of the big labels - Shogun, Critical, Metalheadz etc. I'm sure there are plenty of compilations about.
What kind of dnb are you after? Hospital or Viper have recent compilations which are good for a more accessible cross section of the genre but if you're after something a bit deeper, check out Ingredients, Metalheadz and Critical, all of whom have put out compilations semi-recently.
The recent lp on ingredients was a nice collection of tunes. The Drum and Bass Arena put out a compilation that definitely has a party vibe but is a huge collection of tunes for the money. I think there like 65 tracks on it.