It's worth it. For a hockey junky like me, who cannot get Center Ice from his cable company (damn you Videotron!), little tidbits of games here and there is like an alcoholic drinking spilled beer in an ashtray. You know it's sick, yet you can't help it.
Plus they do have very good hockey coverage (duh) with regular news and updates and special programs and analysis (ie: a whole week devoted to the history of a Canadian team, a season recap, etc.).
And they also show the replays of games old of a few days. That's great when there's a team you don't get to watch too often because of the association and just want to enjoy yet more hockey on a boring day, even if you already know the outcome.
Of course if you can afford Center Ice, go for it, I'll switch as soon as my annual contract with my cable company runs out so I can get Bell Express Vue and become a TV freak spending around 10 hours a day watching games (slight exageration).