Just under 2 years ago.
1. I was having trouble motivating myself to ride, and felt like I needed something new. I had already converted a mountain bike to single speed, and Mr. Brown's site pushed me over the edge to try something new.
2. I skipped the conversion step. After pricing ENO hubs, and other options, I finally just jumped in with an NYC Bikes CityFixed due to the Low cost of the frame.
3. I live in Boise, ID. When I built my rig, I had seen 1-2 other bikes around town. 2 weeks after getting it running I went to my first alleycat which had about 20-30 riders and 10 people on fixed gears.
4. Isn't this the same question as #1?