1. Over the air downloads via 3G (and Edge) are limited to 10MB
2. Not only does the mobile iTunes store lack the ability to filter larger podcasts, but nowhere is the size of a podcast shown!

I can kind-of-sort-of-perhaps see the rationale behind limiting download sizes, both to alleviate strain on the AT&T network and preserve battery life (more the former than the latter I suspect), but not being able to filter non-eligible podcasts (manually or visually) is a big usability issue if you’re on 3G.

But wait! In 2.2 there’s another podcast option that I don’t believe has had much press:

Tapping the name of a podcast will cause it to stream instead of download, with no 10MB limit involved (so much for the battery life theory).  At first I thought this was only a preview, but you can listen to entire shows and even watch video podcasts – which are full quality and not lower-resolution as Youtube videos on 3G are.

This would be super cool except for one thing – this mode almost seems a little unfinished for a couple of reasons.

1. It’s practically hidden – no music-store-like play buttons. I only found it by looking to see if there was more info for shows (like size!)
2. Playback doesn’t occur in the iPod App, and while you can return to the home screen without stopping playback headphone controls do not work (instead they start the iPod playing!).
3. Only certain podcasts appear to work with others returning errors about invalid formats. (This could be a network issue though – my 3G fluctuates a lot at work).
4. Unlike the iPod App, video is only supported in landscape mode. A minor niggle but there’s a podcasts with video or graphics that I like to play at work and glance at on my docked iPhone.
5. Videos remain in high-quality on 3G, whereas Youtube intentionally delivers lower quality versions even on 3G.

Very interesting!