I got the opportunity to play through Castle Ravenloft with a couple different groups of people at the PAX convention during the first weekend of September and was thoroughly impressed. The game is a great one-nighter for anyone who's played Dungeons and Dragons before, and a quick and easy introduction to the role-playing game for anyone who's never played before. Themes and some basic mechanics from the D&D game are kept in place, though greatly simplified allowing players of almost any age to jump in and have a great time. I probably wouldn't recommend trying to play with kids under ten though, the game is a bit harder than the average board game.
The game includes a large number of unpainted miniatures that are to-scale and pulled from various past D&D minis products, so even if you're unsure how long you and your friends will stay interested in the game, it still has great value for fleshing out any other D&D genre games you might play.