I bought both Boom Blox games (that's a lot of 'B's). Those games were...ok. I kind of feel like Wii owners were so desperate for a decent 3rd party game at that point that they were willing to latch on to anything (I know that's why I bought them). That's not to say that the Boom Blox games weren't good; They were good enough to be that 'anything' that people were willing to latch on to, but I feel they got more attention than was really warranted.
Did you get to try the multiplayer modes?
I enjoyed the Boom Blox games in single-player mode because it made good use of the motion controls and was quite charming... but the single-player mode alone wouldn't have sold me on the game being one of the "best of" for Wii. However, some of the mutliplayer games really stood out and the ability to further create and share levels made this game is a perfect example of taking a simple idea and then polishing/expanding it until you have a full-featured package that is more than the sum of it's parts.
Then again, maybe my love for Boom Blox is just a manifestation of my inner child who obviously never got over the urge to knock over a stack of blocks that someone else carefully assembled. If you actually have grown up then it's possibly you'll never derive the same enjoyment that I do from the game.