I'm in the same boat with Bruce. My WRs are Chad Johnson, Joe Horn, Steve Smith, Keyshawn Johnson, and Bruce. I've been starting Chad and Horn, naturally, and have been going with Smith over Bruce recently. Smith is a bigger scoring threat and since there's a big drop-off to the #2 WR in Carolina, Smith almost always gets his yards.
Not that Bruce is a bad start any week. He still has tons of yardage, but in fantasy football it's the TDs and those have been scarce. I guess it's due to the chemistry Bulger and Holt have, and the fact that Holt is really emerging as one of the best WRs in the game now. Faulk's return could help or hurt Isaac's production, we'll have to wait and see.
For now I'd strongly recommend Smith over Bruce most weeks.