T.,
I work full-time as well, and I waited until my son was ready to potty train versus trying to train him on my schedule, because 1) I figured it would be too hard to do over a weekend and 2) so many friends had shared their tales of woe with me that honestly I was really dreading the process. We did have a little potty chair in the house from the time he was a year old -- my nanny was Eastern European and said that's when they start training where she's from, so she asked me to get one -- but we never really encouraged or pressured him to use it. I did buy the potty books and a video when he was around 2-1/2, but again, just read and watched them with him, never really made a big deal about him using the potty.
When we were on a two-week family vacation with my parents last summer, one night he just announced that he wanted to use the potty, so we took him in and he went poop. We made a big to-do about it, the whole family coming in and cheering, and that was that - he was trained in a day at 3 years, 2 months old. No bribes, no battles, no drama. We had him in Pull-Ups at night for about a month, but other than that he's had maybe 2 or 3 accidents ever. He's never had any issues with going poop and even can wipe himself pretty successfully (thanks to his fantastic pre-school teachers!).
Every child is different, so your son may well get there way before mine did, but my advice is to educate him about it now but wait until he is clearly ready to use the potty before you start taking action. It made the experience so much more pleasant and stress-free than I ever imagined it would be. I have a 22 month-old daughter who hasn't demonstrated any signs of readiness yet, and that's my plan with her as well.
Good luck!