Might as well bump this thead while Im at it.
SOAD are awesome, fave album is probably Mesmerize/Hypnotize (I consider it one album). But all their albums are great, though I must admit I haven't given Steal This Album a proper spin. Serj Tankian is one of my fave singers (though not a very gifted one, technicely). I just love the middle-eastern sound of his voice. Also the vocal melodies on especially Mesmerize/Hypnotize are very well written, when Daron and Serj harmonize it often sounds brilliant, or at least really good. Daron is a very underrated guitarist IMO, at least I don't see him highly rated often (not counting SOAD message boards). He really has a good feel for tasty, original riffs and melodies.
The rhytemn section also does it's job very well, the bass is often very basic, but it fits the music perfectly.
Fave songs: too many to choose.