I've got very ecclectic tastes and will watch (and have watched) just about everything. I can't pigeonhole myself and tell you excatly what I like, but I like a mix between mainstream stuff and artsy, indie stuff. I'll watch films from any decade, but I think the 1970s is the best decade overall cinematically.
I do like road movies, movies that take place over the course of a day or just a few hours, and character studies. If I HAVE to pick actual genres, then gimme blaxploitation, most (but not all) horror, crime dramas, some sci-fi, and genre mashups, or movies that tweak genre conventions. I'm also a big fan of long takes, tracking shots, dolly zooms, and great cinematography, framing, and general camera work/movement. My favorite cinematographers are Roger Deakins, Wally Pfister, and Robert Elswit. My favorite editors are Sally Menke, Roderick Jaynes, and Thelma Schoonmaker.
When it comes to my reviews and ratings, I used to prefer the 4 Star System, or going by letter grades, but the 5 Star System has grown on me. I generally am pretty generous and favorable with my reviews, preferring to look at the good over the bad, and I try to look at the work as a whole, which is why I'm usually forgiving. I will not hesitate to get critical if something really bugs me, though. Generally I don't recommend a movie if I give it less than 3 stars (on a 5 star scale). If I give it 3 stars, then that is the bare minimum for recommendations. I use to not recommend anything with less than 3.5 stars, but I have changed my views, so, as a result, I'll probably have to go back through the archives and update everything at some point.