We started somewhat accidently(no pun intended!) but quickly realized he "gets it" and decided to stick with it. The unexpected weather has caused us to be home and inside more than I anticipated so it worked perfectly with getting the potty training going.
Lucas has only had 4 accidents in 3 days- pretty good in my book! After doing it with 2 kids, my opinion is that going straight to underwear/panties is the key to potty training. Pull-ups or whatever only slow the process. It also helps to have a big sister willing to participate in the learning process...as long as she gets Skittles, too!