LOVE IT! I did my first (and only ) marathon via his run/walk program. I did 7/1, finished in 4:21, and played an hour of field hocket the next day. I had fun THE WHOLE TIME I did the mary, and had no injuries, no DOMS, no nuthin' but positive experiences.
Heard lots of great stuff about it and had a number of friends use it with success. I've never been able to get it because after about 30 minutes, if I stop to walk, my legs don't like to start again.
I am using it right now to train for Disney... I like it. Slow build up, short, medium and long runs... I used Hal Hingdon's program last year and I liked it too, very similar.