Just hiked over at Willowdale and I'd give it 70-30. 70% dirt - 30 snow. The snow was crusty and rideable. The snow was firm under foot. The dirt was dirt - not mud and as the weather is going to be colder over the next few days I'd say conditions will improve for the dirt. It looks like the fire road areas are mostly snow though as they were packed down by users. Single track is good to go I'd say. Some icy spots to keep you awake. Have fun!
I've been walking it too and think some more time is needed before a weekend crowd descends, maybe another week. Under that 30% snow is water or ground with the frost coming out of it. Unless it's frozen like it will be tomorrow morning. There are alternatives - Cape, RI, Dogtown, etc.
Just rode at Willowdale today and I'd like to revise my trail estimate. There are some sections of trail that are very snowy. None too deep though. Maybe the trail was more like 65 - 35 in make up. There was some mud as the temp was around 34 degrees. I would also remind everyone to use their own judgement when riding a trail at this time of year and not going when it is too muddy. Also, I always forget this - ride early in the day. As in before noon so the snow hasn't gone to slush from the sun. Had a good ride that kept my attention as snow is infinitely variable. Especially in the corners! Have fun out there.