I've seen some hints of this happening and initially I was concerned. Apple removing Podcasts from the mobile store is a pretty big move and I was concerned that it would see a big drop in discoverability.
However, if Apple are going to make it a separate app it could help highlight the medium even further to people—they're no longer in the purgatory of the 'more' button. What would be even better is if the app comes built in with iOS6 (like the Videos app) or is promoted by a pop-up like iBooks at least.
I hope to see more news of a standalone as the Beta progresses and not that Podcasts are being led around the back of the barn..