I've been up here several times with a group of friends and I've never been disappointed. The cabin itself is beautiful, with its log walls and big balcony. It's got several rooms, so you can comfortably fit more people than you'd expect. The top floor is basically one big master bedroom, the main floor has two bedrooms and the space you see in the pictures, and the basement has another living room and two or three more bedrooms.
I love Great Barrington's downtown, which is only a five to ten minute drive from the cabin. It has lots of great restaurants, cafes, and shops, though the loss of the Gypsy Joynt will sting.
There is great hiking nearby, which is usually the point of our trip. Our favorites are a 2, 2 and a half hour mountain hike in Great Barrington and a roughly 30 minute hike that straddles the New York/Massachusetts border and ends at what I believe is the biggest waterfall in Massachusetts.
I've never been in the winter, but I hope to do so soon. Every time we drive by Butternut I wish it's sky season.