Transworld and Snowboarder
Check out the major snowboard magazines, or better yet their websites. At the beginning of the year mags like Transworldsnowboarding and Snowboarder send out their pros to ride all of the snowboard companies new sticks for the year. Then they rank them. With new styles like V-rockers, alternate/reverse camber, etc., this is the best way to find the best board for you compaired to your budget, skill level, and type of riding you prefer (park, freestyle, all mountain).
Seriously look into Transworld's "good wood" and snowboarders "best of test". Even if you aren't in the market for a brand new board, you can still look up what these magazines thought of the 2008 or 2009 models through archived lists