I downloaded version 4.9 of iTunes today that contains support for Podcasts. Overall it seems ok, very easy to use but no support for Bittorrent which means I'll be sticking with nimiq for a while yet to keep up to date with DotNetRocks. For more information about this version, take a look at iPodLounge.
For more info about how to get your RSS feed integrated with the iTune Music Store (and iTunes specific tags), see http://phobos.apple.com/static/podcast_specifications.pdf.
UPDATE:Carl Franklin has just posted a comment to say that DotNetRocks has reverted back to standard download feeds to allow people to use iTunes as a client while the Bittorrent thing is sorted out.
.NET Rocks! no longer requires bittorrent for podcast downloading. It's both a blessing and a curse, as we're once again maxed out, bandwidth-wise. As soon as BitTorrent goes into iTunes, we'll switch back.
Carl
I sure hope it comes.