I've had my '04 Cavalier for a little over 40K miles and has proven to be a great car, anywhere and in any season. I bought the car in March '05 w/28K on it, traded in a '99 Malibu. The thing I like most about the "Cavy" is the gas mileage both city and highway. I've got it up to 39mpg once, and now that I live 3 miles from work, I only have to fill the tank once every two weeks, which is good considering gas prices. Other things I like are the handling and V6 like acceleration that comes from the low maintenance, high efficiency 2.2L Ecotec engine.
Gas mileage, acceleration, handling, and the 2.2L Ecotec 4 cylinder.
Better interior styling and suspension, but then again why bother, the Cobalt's out.