I tried Podcast for several days and have deleted it from both my iPhone and iPad.
What I liked about it:
- Clean interface
- Easy to search podcasts
- Easy to subscribe to podcasts
What I didn't like about it:
- Laggy
- Artwork not always downloaded
- No Settings for me to adjust UI, playback, etc.
- Not enough playback speed options
- Not enough playback skip options (want more than 30 sec. in either direction)
- Podcasts often reverted to unplayed status even though I had previously finished them
- Playback did not always pick up where I left off
These are just a few items of the top of my head. I think I've been spoiled by the Downcast app and the controls it provides (not an advertisement - I just prefer Downcast to the other podcast apps I've tried). I'll gladly give Podcast a try again once iOS 6 is released, as I would expect that by then it will include a host of improvements.