I hate when people don't follow up on their question threads so for whatever it's worth, here's what happened:
So we arrived in Wawona on NYE about 3 pm. Lots of snow around the gate but very little in Wawona. Camped on dry-ish ground. (well, slept in the truck, but you know...). Stayed up hootin' and hollerin' around the campfire until midnight (The campground was nearly empty and the two other groups were up as well, I figure NYE is the one night that the quiet hours in a regular campground don't apply....).
Woke up new year's day to a beautiful falling snow. About 3 inches had stuck overnight. Our plan was to throw on the packs and go into Mariposa grove for an overnighter in the snow. The snow turned to rain. A lot of folks had really wet gear (I had brought a second set of gear - all my old stuff - for the car camping part, so all my snowcamping stuff was nice and dry and packed away). They didn't seem too excited about packing it all up and hauling it in to the grove. So instead we dayhiked and had a grand time (hard not to have a good time with this group). Snow was falling heavily when we got back to the cars around 3 pm.
After a brief stop at the wawona hotel after the hike (fireplace after a wet hike = nice. Bar service not starting until 5? Not so nice. Was looking forward to that beer...) we went back to camp which had turned into a wet slushy mess. And it was raining. The temperature had climbed during the day and we really wished it were a bit colder and snow instead. Oh, the nice lady at the Wawona Hotel had told us the forecast had changed from a couple of inches to three feet (!) of snow that night. So you can see where this is going - we packed up and headed out that night.
Kind of disappointing to bail on part of the trip - this is a strong and hearty group that has put up with far worse conditions upon many occasions, but I think we were all kind of in holiday burnout mode and ready to get back and start drying out. Still, the hike into the grove was beautiful with all the snow and of course I never have a bad time with this group of friends. I'm sure lucky to have a big group of friends who not only *doesn't* look at me like I'm crazy when I suggest standing around in 20 degrees on NYE and then camping in the snow, but eagerly wants to join.