Hey, Patti,

H.264 is supported by Sorenson, though it's called either MPEG-4 part 10, or Quicktime/MPEG AVC depending on which version of Sorenson. (H.264 is the encoding standard, AVC is Apple's name for their codec implementing that standard.) The Quicktime encoder software supports it, and I'd be very surprised if Vegas and Canopus don't also.

There are also a bunch of players that support it. Quicktime is the most well known but there are quite a few others as well. That's one of the things I like about it, you're not limited to one single media player or a single OS platform.