I have run the full, and the ToT 13k. Do they say no iPods? I do believe so. Most big races do, as it is a liability issue. That said, you still see plenty of them out there. Each year people think that this is going to the be the year they will crack down, but I can't honestly see them doing that w/o advance warning. Should you? I ran the full with 1 earphone in, so I could still hear anything important, but I know that people at the last ToT had their music so loud I could hear it running next to them. Not safe at all. If you start training without it, you won't miss it.
Regarding a dress code, I know there have been people wearing similar clothes to run in. In fact, at the first ToT, they had someone dress up as a gladiator, wearing the helmet, a cape, shinguards, and a Speedo. Nothing else. They got them on the jumbotron, and the gladiator vowed to run the marathon in the same getup. Then come January, who woulda guessed it, I saw the gladiator running again, in the same getup. So as long as you are decent, you should be ok. Check out the past pictures at asiorders.com if you want to see how others dressed.
