I finally got around to checking my logs and stats for a site that has bombed in the Google update. It's basically a (carefully chosen) links site for a number of bands but I publish most of the data as rss feeds as well.
Most pages are in the Yahoo rss directory (available to My Yahoo users). When I get spidered by the Yahoo Feedseeker it tells me how many subscribers there are on Yahoo. I haven't done the Maths to add everything up but I have 1029 feeds subscribed to with up to 135 subscribers per feed (mostly less than 10 per feed). I guess that equates to about 6,000 subscriptions. So, whenever I add items into the feed a good number of users see the latest items.
Since I link directly to the source rather than to a link script I don't get to see any response. I was just checking my Amazon stats (Amazon reviews are a source of information) and I noticed some big spikes where click throughs on a day were five times higher than normal. This coincides with the day after I have updated my pages and feeds. People aren't buying the items they clicked on but that's fine by me - it's an info site that hopes to pick up a bit of money as a sideline.
I'm impressed with the power of RSS to alert users to new info (and new products).
I've seen similar patterns - RSS has a good click through and a good conversion. The site I work on is a normal e-commerce site, and sometimes we see more clicks and conversions from our RSS news feed than we do from MSN, Yahoo or AOL natural SERPS.