For me, Jay Peak...
It's probably, no, it IS my favorite mountain on the eastern seaboard. As long as you're there for the boarding and not the night life, it's the place to go. Great variety of terrain, lots of glades, lots of powder, and the vibe is like you're hanging out with people you haven't seen in 20 years.
I remember last year coming out of some glades and heading for the next set, there's this lifty standing there with a big beard, looks like he probably has worked there his whole life... I nodded at him, he nodded at me, I went into the next forest to find more deep powder stashes. That pretty much sums up Jay Peak.
For what it's worth I live in Calgary aka rocky mountain snowboarding heaven, and I'm wearing a Jay Peak sweater right now!