I do a poor job of following new music, there is just so much great music that has stood the test of time I have yet to hear. So I find myself more researching and listening to older bands and albums (mostly 80's with some 70's and 90's, to grossly oversimplify). But I'll try to think of some 2006 records I really enjoyed.
Ghostface Killah - Fishscale
Sales have been disappointing (as of a week ago the album hadn't even gone gold), but I believe Fishscale has cemented Tony Stark's new role as the dangerous darling of the rock snob critical community. The opening tune, "Shakey Dog", is the most ridiculous hip-hop song I've heard all year, meaning it's intensity blew my mind the first time I heard it, as well as in subsequent listens. Ghost purportedly meticulously selected the beats for these tracks from a pool of hundreds, and they definitely want for nothing. The MF Doom produced tracks (Clipse of Doom and Underwater) are wonderfully bizarre, and even the obvious attempt at a single, "Back Like That", is a pretty good tune I listened to for a couple of weeks. Is Fishscale better then Supreme Clientele? Nah, but its still damn good.
Assemblage 23 - Storm
Futurepop record, definitely not everybody's cup of tea, but the pounding beats, consistently good production, and well-written lyrics with a flair for the melodramatic without venturing into emo-esqe territory were exactly what I needed at one point this year.
Wow, two records, thats all I can think of right now.