It rides great. I took it out to Great Brook Farm today, and rode around on the handful of trails that stay open to bicycles in the winter. Those trails see lots of hiker and snowshoe traffic, which packed the snow down to provide a pretty firm surface, most of the time.
The tires hooked up great, in those conditions (I had them at 15psi). Traction was actually better than what I usually experience in dry summer conditions. The fixed drivetrain was neat, too -- while the inability to coast (and rigid frame) made me take descents pretty slow, the rest of the time I really enjoyed the feedback and modulation it provided. It was particularly amazing on the climbs. I didn't fail at a single climb all day.
Overall, it was a great time. I went out expecting to ride one or two laps and be so exhausted that I had to stop. I did 3 and felt like I had energy for more.