I hiked Wilson today, intending to do a solo lollipop loop, going clockwise up the Mt. Zion Trail, then up to Wilson via the Sturtevant Trail. About 2 miles from the summit, I encountered ice on the switchbacks. It stayed pretty icy and fairly slippery until the last little push to the top, where it was then sinply snowy.
I met two new friends on the trail, and while they did not have crampons, I did. They were not absolutely necessary but they were handy, and I highly recommend hikers use them and poles or an ice axe as safety precautions until that ice is gone. After all, I did plan on being solo the whole day, so I tend to be a bit conservative so I'm never that solo hiker you hear about on the 11 o'clock news.
I decided not to finish my clockwise loop as planned. Instead I joined up with my new buddies and hiked down the Wilson Trail. There was some snow and ice near the top, but once we got to the road, we were in the clear.
It was a beautiful day, with excellent visibility. We enjoyed great views of our local snow covered peaks. Check out my pics if you'd like: www.flickr.com/photos/33777171@N06/sets ... 749294482/
Mt. Wilson Trail Report
I'd guess the temps near on on the summit were between the upper 30's and low 40's. It was pretty darn cool in the shade, but we did get some nice, warm sun on the summit. I wore long underwear bottoms all day, which I typically only do if the temps hover around the 30's or below. We had a very light breeze occasionally, but mostly it was still. 
