A thought on feed readers versus the social web
It's become common for bloggers to announce their new entries by posting little announcements to places like Twitter and Facebook; the ultimate version of this is the Planet Sysadmin twitter feed. Even beyond how common this is, my vague Referer-watching here on WanderingThoughts suggests that readers actually use this.
(Although a certain amount of the hits are from robots; for some reason, harvesting URLs from Twitter streams seems popular.)
In fact, anecdotally a fair number of people have switched from feed readers to finding out about new posts through Twitter and Facebook updates. On the face of it this sounds vaguely crazy, which makes me think two uncomfortable thoughts about why people could be doing it (especially for something that's already an aggregated feed, like Planet Sysadmin).
First, it could be that most people don't actually want to read all of your entries most of the time. Instead, they prefer to skim over a short headline and click through only sometimes, if they're sufficiently interested. In theory this could be done in feed readers, but in practice most feed readers seem to put obstacles in your way for doing this sort of fast skimming, some of them subtle (for example, even having an 'unread' state for entries).
Second, it could be that people actively prefer the web browser experience (and haven't found web based feed readers to be compelling). I can sort of see this, especially in the modern world of heavily tab based browsing. I suspect that when you get down to it, few feed readers provide as good a user experience as opening a bunch of links in a bunch of tabs and then going through them; you get random browsing through them, you can pause your reading of one entry and go to another without losing your place, you probably have less space eaten up with administrative clutter, and the result may well be prettier.
(This leads to some thoughts on feed readers themselves, but that's another entry.)