FYI: if I manually refresh podcast subscriptions in iTunes 11.1, the program seems to hang for about 90 seconds. The current song keeps playing, but you don't see movement in the progress bar; the spinning beach ball sometimes appears. In the Podcasts List pane, you at least see little spinning circles next to all the podcasts, so you have a sign that something is happening; in the other Podcasts panes (My Podcasts, My Stations), there's a little arrow in the upper left corner that makes a small turn/jump every 30 seconds or so but is otherwise static, so it's kind of hard to tell whether or not something is happening.
This is worse than with the previous version of iTunes, but not that much worse - iTunes has never exactly been speedy.
But anyway, nowhere near as bad as what you're facing.
Are there podcasts only on your iPod that you care about losing? One approach may be to delete the Podcasts app off your iPod, and see what happens upon syncing then.