This is a VERY interesting topic. I didn't learn about EC until my FOURTH child. By then I had a 4 YO, 3 YO, 2 YO and a newborn. I was just too busy to EC. (For those of you who don't know, EC is early potty training. The idea is that we train babies to use their diapers and then we have to retrain them to use the potty, why not just skip the first step?!)
Some women EC when the baby is a little older (say, 6 months.) There seems to be certain stages that are good to start and if you miss that stage then you diaper until you catch the next one. Most EC moms use cloth diapers, and that seems to be easier to potty train. Use fitteds without covers if you want to EC WHILE using cloth instead of bare bottoms. I'm sure there are EC boards, check ivillage.com
A friend of mine ECs. Her 4 YO and 2 YO are both potty trained, have been since they were 15 months or earlier, and she has a new baby now.
My girls potty trained at 4,5,4 and the youngest is 2 and not yet potty trained. So....if you have the time to really focus on the EC it might be worth it. To me, I'd rather change diapers and potty when the child leads. I've used discipline, removal of privileges, bribes, and in the end they only potty trained when they wanted to. If I had used EC, though, perhaps they would have potty trained much sooner.
S., mom to 4 girls on Earth an 5 Heavenly treasures!