Call of Duty: World at War is more than a rehash. It provides a refreshing change to the well known maps and weapons from Call of Duty 4: Modern Warfare, and makes some positive changes. The single-player campaign involves a riveting and emotional story, and the inclusion of co-op is fantastic. The game itself however is heavily weighted towards multiplayer, as was its predecessor.
Ups:
Based on the fabulous Call of Duty 4: Modern Warfare engine. Spectacular multiplayer, and the option to search for games locally. Excellent change of scenery to WWII, very solid single-player. Co-op.
Downs:
Single-player a little short, WWII setting won't appeal to all. Weighted very much towards online play (if this can be considered a bad thing).
9/10