Not yet, but they will be after another season or two when they enter rebuilding. The Red Sox are set up to be one of the best teams in the MLB for years to come, and the Patriots should be very well off until Brady (or Bellichick) retires. The Bruins kind of had a magical run, I think, so it's possible they could go back to being just a middle of the road team like last year, but this championship will definitely rekindle interest in them.
The Celtics are going to return to the basement soon (with the Revs being permanently stuck in the sub-basement).