Basically, the film immediately tries to be appealing and watchable, first by trying to wrap everything around "rules" that appear on-screen. I found this to be equally annoying as comical (Zombie Kill of the Week, though, you have to give props for being totally ridiculous). Same with the zombies are black-bile drooling freaks, who set their eyes on a target and go after it like nuts. Seems kind of like what I've heard regarding Danny Boyle's "28 Days Later" (I think I heard it from Aspergian Sarah) and "running zombies." Anyways, you can see how many unsuspecting people get rendered undead. Oh, and they go for goading consumerism with the whole Twinkie meme, which probably will cause some people to go out and "enjoy the little things" at their local convenience store. It's so "integral" to the plot that I'm being less than cynical.
Now, I should get on to describing the plot. Jesse Eisenberg, the audience's kind entry point to Zombieland USA, is walking around after he's lost his car and apparently his family to zombies. He meets Woody Harrelson, who's driving a Lincoln Continental with a huge snowplow and who's a veteran when it comes to this stuff, even a zombie sadist (as another friend said, there's an interesting variety of zombie kills in this movie). Harrelson and Eisenberg take the two extremely annoying nicknames of Tallahassee and Columbus, which they'll be called for the whole movie, due to the destinations they're supposedly trying to reach. They find two sisters as well, who they call Wichita (Emma Stone) and Little Rock (Abigail Breslin). You'll find these two are experienced con artists, and they even play the same sort of trick that Nicolas Cage and Alison Lohman do in "Matchstick Men." Wichita will also become the lover of Columbus, resulting in scenes that are pretty sappy and remind me of "Adventureland" (Eisenberg's other recent film, which was better).
For some reason, all of the "destinations" are on the East Coast, but the sisters decide to make a U-turn and go all the way to Pacific Playland in Los Angeles, because it "reminds them of their childhoods." I can somewhat excuse it in a zombie film where there is no direction whatsoever, but usually it would be considered pretty contrived. But first, they randomly make a stop for shelter at not anyone's old house to spend the night (I don't get this whole thing). You are probably going to get mad at me for telling you who it is, so I'll just say a coda about it at the bottom, regarding its semblance to a video I saw a long time before this movie.
Anyways, a long-feeling portion of the film is spent here, and the climax, which is contrived with good cinematography. Ruben Fleischer, the film's director, loses control. The movie gets a lot less interesting than the beginning. Now for the technical stuff. Harrelson was good, Eisenberg was pretty decent, Breslin got a little annoying, and Stone I don't think I was crazy about either. It's a Harrelson movie, pretty much. I don't know, though, if I'd take the time to see it. Funny for a while, but getting so random and just unexplained it doesn't work. Even "Shaun of the Dead" had a better hand on its plot. C+
Don't look on the IMDB page if you want the twist to be kept secret
CODA (SPOILER ALERT; REGARDS "MAIN TWIST," as it has been called): The person in question is actually Bill Murray. I thought it was kind of funny when Columbus mistook him for a zombie (saying a line reminiscent of "The Tuxedo" and James Brown), but the section didn't work beyond a certain point and felt just a like an advertisement for Bill Murray dripping in hero worship. Here's the video I was talking about that has him in it in a very similar situation (that doesn't involve zombies). Pete and Brian beat them to the punch, apparently.