[quote name='BattleChicken']I'm starting to get the impression that brawl will be a LOT more... invasive, In the sense that the action will get interupted by so many stage mechanics more than they were in Melee.[/quote]As far as I can see there are two types of interference. Passive and Active.
Passive is what the game is all about that's the Pokémon Statium changing to different modes or Zebes where you can break the stage in half. I don't think anyone minds that if not for that we'd all be playing on Final Destination and if I've learned anything it's that tourney level players don't move off FD anyway so it doesn't matter what the other levels are like.
In terms of active interference Melee has a few of those as well which most people didn't like. Poké Floats, Big Blue, Icicle Mountain all kill you if you don't move which I found annoying but MKII, Venom and Coneria all had direct active interference as well and they were fun (well Coneria at least). I'm not to worried about the "!" until they show what exactly it does?. Probably no worse than the Pokemon stage in SSB.