Brandon Savage has posted a reminder for those interested in caching in their WordPress installations - he'll be giving a webcast (as a part of the TEK-X series) on just that.
On Friday, I'll be presenting a webcast called "Caching for Wordpress." In this webcast, we'll talk about ways to make Wordpress perform better, including aspects of caching from the application perspective and from the content perspective. There will be a discussion of caching plugins available, as well as a discussion of the Wordpress API and what it offers by way of caching opportunities.
The webcast itself is free but you'll need to register for a spot if you'd like to attend. While you're there, you might also sign up for a few of the other webinars in the series like al Evans' talk on remote developers or Scott Macvicar talking about Facebook's HipHop tool.