The GoodThe typical Rockstar stories and characters, the decent graphics, super fluid gameplay, and the fact that it revisited the western genre (of the spaghetti variety) for a quick market probe that, i believe, eventually contributed to small but significantly enjoyable western offers of the last few years: Gun, Red Dead Redemption, Call of Juarez, a few films as well.
The BadGameplay is somewhat repetitive, although I may have been spoiled by the fact that I bought this well into the Xbox 360 era and so my standards for gameplay variety in a single title may have been much higher. Also, the duel mechanics aren't that much fun (try again ad infinitum), and the difficulty curve is actually a zig-zag. The infamous cannon level with General Diego is a perfect illustration of how poor difficulty balance can prevent people from finishing a a game out of justified frustration.
The Bottom LineAs a preliminary Red Dead Redemption, minus the GTA inspired bits. Imagine Sergio Leone's style applied to multiple converging storylines, soap style, and then add a healthy dose of weird west.