My review system will be sort of a curve. Since there are 10 possible ratings about 10% percent of the albums will get a 5, 10% percent will get 4.5, 10% percent will get 4 and so on...
Realistically, this isn't exact and you won't see me rate many albums 0.5 to 1.5. They are out there but I don't bother listening to garbage, and I won't rate something unless I've heard it many times. The 5s are also a little bit harder to come by but that's the basic outline.
My taste is hardcore, gangsta rap mostly but I like all types of hip hop overall. From Uncle Murda to Charles Hamilton to Waka Flocka to W.C. to Sage Francis to MF Doom to One Be Lo to Aceyalone to De La Soul to Slick Rick. I do prefer hip hop from 1997 to current because a lot of the older stuff sounds dated in my opinion. So as much as I appreciate old school hip hop, I'm not one of those people that says hip hop is dead and that the so called Golden Age produced the best stuff.
I rarely listen to stuff pre-1992 of course with certain exceptions. My favorite years are probably from 1996/97 up until about 2000 but the Naughties have some of my favorite albums as well.
I don't really listen to instrumental hip-hop and won't review Greatest Hits albums.

As far as other genres, I listen to a little bit of everything and especially R&B. However I don't know other stuff nearly as well as I do Hip-Hop. I think I am a bit of a Hip-Hop academic but not all that knowledgeable about other music. Still, at times I will review and rate other genres. Also might start reviewing films and shows at some point. I'm a huge TV fan so we'll see.

My favorite albums since 2000 of the top of my head(as of April 2011):
Sean Price - Jesus Price Superstar
Superstar Quamallah - Invisible Man
Freddie Gibbs - Midwestgangstaboxframecadillacmuzik
Cannibal Ox - Cold Vein
Ghostface - Supreme Clientele
One Be Lo - S.O.N.O.G.R.A.M.
Madvillain - Madvillainy
Scarface - The Fix
Jay-Z - The Blueprint
The Game - Documentary
Beanie Sigel - B. Coming
and so on...

Also I'm trying to add as many prolific hip hop inclined users to my friends, to be able to make intelligent charts.

Right now my mission is to properly review some of my most beloved mixtapes that don't have many reviews on here.