Why are you pissed? Are you that overqualified that putting you on the waitlist is simply unthinkable? Even if that were the case, there really isn't any reason to be pissed - you're applying for admission, not demanding it.
In general, it's best not to say f*ck you unless absolutely necessary. You never know when you may need something from someone...
I do understand what you mean though about burning bridges. You make a lot of sense when you say that. However, I understand hushpuppy too. I mean, a freakin' dean tells you twice that you should look forward to a scholarship and then decides to waitlist you? C'mon, I will be overly pissed too and seriously, I really dont know how I would have reacted, probably worse than hushpuppy? I dont know. Well, too late now, Hushpuppy the good thing is, those suckers will know how you really feel. about time someone told 'em the truth. On the other hand, your relationship with them is sour for life. Lets hope it does not spill over.