I'm thinking about buying NBA Broadband -- any reviews?

Are you talking about NBA League P? If so, then its pretty good. Resolution and quality are very clear. I've never had any problems with watching games (really just depends on your internet connection). The only drawback is that now you have to choose 10 teams for the entire season to watch. And you can't go back and change them! Once you pick your 10 teams, you're locked in. So if you want to watch many different games from your laptop, then it will definitely have you limited. But if you just want to watch your favorite team, then it doesn't matter. I've never had MLBTV so I can't give you a comparison, but i'm guessing it will be basically the same quality as NBA League P.