Best Paid: BeyondPod
This app rules for many reasons, including:
1. configurable categories
2. responsive and active developer
3. free trial with full functionality
4. playlists
5. allows download or streaming
6. can automatically delete files when done listening
7. can see lists by podcast, category, or all
8. lots of information elegantly displayed - i love the played progress monitor on the podcast lists
9. lots of configuration options, like when to update each category/podcast, how many to download, download when on wifi, etc.
10. Download queue management coming according to developer
I chose this over doggcatcher because dc didn't have a free full-featured trial that I could find (might be different now). Also, does dc have configurable categories? For someone who tracks lots of podcasts, this is essential.
Even though price of bp is steep, it's a great player, I use it every day on my commute. Decent 1x4 widget too.
Best Free: dPod
Listen can't handle vidcasts, and has cluttered interface. dPod is way better. I think I tried acast way back, but rejected it in favor of dpod. dPod has improved over time.