This is entirely based on my 1st or 2nd time on these mountains:
Stratton - Typical VT mountain with good descent, decent runs, nothing impressive but nothing terrible either.
SugarBush - First time there it was pounding in snow, I actually was riding in real POW for 3/4 of the day shredding it up since it was coming down all week long. Very country oriented place and service all around, friendly people. Me and my bro gave it two thumbs up and plan on going there twice this year.
Killington - Expensive but really, so is a lot of VT in general, the difference is in what 10-20 dollars? Long long lonnnng trails if you like to explore around and not all about park, big plus. Lines got crowded sometimes but nothing out of norm.
Mt Snow - Been there 15 years ago and last year to give it one last try, same impression both times. Way hard packed, icy, and lifts seem to be placed in odd out of reach areas at the bottom of the mountain resulting in me having to kick it over a ways (just my 2 cents). Never tried the park. Won't be a third time
Okemo - Good food, good lifts, mountain overall good versatile runs. This was in mid march of '07 so it was sunny out all day long and warm, so it got mushy at the end of the day and not all runs were open. Overall a good resort and would go back again.
Waschusett, MA - Mountain wise, nothing bad, another typical decent size mountain for anyone in the area since there is nothing better in distance unless you travel up to VT. Cons, pay for parking, (15 or 25 I can't recall, should be free so they fail there) unless you park at the very very bottom where the buses do. Prices as well for a resort of that size contrast to ones I've been to in NY for that size, overpriced. Moutain is good, prices a killer.