Here's a Honeycomb-specific app you won't find in the Android Market just yet -- the popular podcast player BeyondPod has an open beta for testing the tablet optimized HD version, and things are shaping up nicely. A couple of us here have been fooling with it for about three versions now, and it looks very close to release-quality. Certainly working well enough for me to recommend you guys give it a try.
It has the features you expect from BeyondPod, but scaled beautifully for the big screen of a Honeycomb tablet. Widgets, high-speed playback, favoriting, and tabbed navigation make this one a real standout. Will there be bugs? Probably. This is a development beta, and if you download and install it you're actively participating in the testing. But version 2.70.10 (latest as of this writing) seems really stable and the features are all there. Hit the source link for full change logs and the download.