I can't imagine Jay selling to a non-ski industry entity. I would imagine this will be between Alterra and Vail, and with Stowe so close, a less than ideal buy for Vail.
Jay is going to get sold to whoever offers the most money, ski industry focus or not. If anything, Jay's non-skiing four season build out probably makes it even more attractive to non-ski specific resort companies.
Stowe and Jay are very different markets. I don't see much overlap between the two areas and Jay has a massive non-ski season setup now, something Stowe won't ever have since they cannot develop the Mansfield side of the resort.
If you are thinking about two nearby areas competing on the same season pass... Alterra might be the least likely since they already have Tremblant for the Montreal market. Having Jay would split that market between the two areas (again, though, two very different areas). On the flip side, perhaps that helps steal passes away from Orford, Sutton, Bromont, Owl's Head, MSA, etc. if they can offer Montreal an even better one-two punch? However, I continue to see these multi-mountain passes not as northeast focused but rather the focus is on getting the broadest amount of skiers to fly west and stay on mountain at the big western resorts.
I am sure all of the big players are considering it and deciding how much they can offer. Jay would be a great pick up for any of the major players and is pretty much the last major NE resort with big value left.