I found an interview with Steve Jobs that answers the YouTube part of your question.
Markoff: “What about YouTube–”
Jobs: “Yeah, YouTube—of course. But you don’t need to have Flash to show YouTube. All you need to do is deal with YouTube. And plus, we could get ‘em to up their video resolution at the same time, by using h.264 instead of the old codec.”
Here is a
link to the blog that I got the quote from. Keep in mind that the items listed in the FAQ are as of 1/13. Some of them may/will change by the time the iPhone is released.