I haven't purchased this game yet but had been thinking about it. I heard it won some awards but I wanted to know exactly why because I didn't hear it was the best boardgame ever.
It's a dungeon crawl with first rate components that plays in 1-1.5 hrs. That feat is hard to match.
Although the game plays great with its base rules, it ALSO has unlimited potential for customization. That is another incredible feat--it is both a complete game and a tool kit for more gaming.
Another positive testimony to CR is that it has inspired some terrific homemade content. I couldn't help but write my own custom adventure that you can find in the files section for CR ("After Him! A Light Campaign for Castle Ravenloft"). I'll let you be the judge on how that one plays, but some of the other custom scenarios are brilliant. Some on here say that custom adventures prove that it needs tweaks, but I disagree. I think many of them are evidence that players really enjoy the game and made time to take advantage of its toolkit qualities.