Twitching, as you're aware, is not a hobby reserved for the internet. Its origins lie in the bird world, and after a quick scout to twitch the activities of the twitchers, I have discovered that, (gasp!) the feather-loving community is using RSS to share bird information among themselves and other bird minded individuals.
Just one example from many, Birding.uk.com (...that's BIRDing...I'm guessing/hoping it's another way of saying twitching) has an interesting RSS feed for online ornithologists. Be assured that adding it to your MIX will open up a whole new world of birds (the feathered kind, of course).
WebTwitcher's Recommended Twitch