Automattic Stats plugin for WordPress...
Blogs hosted on WordPress.com have a nice statistics module that integrates into the dashboard. Yesterday, the folks at Automattic released this as a standalone plugin for self-hosted WordPress blogs. The developer, Andy Skelton, has more info.
Installing the plugin is really easy - copy the file into the plugins directory, activate it through the dashboard, and enter your WordPress.com API key - a process almost identical to installing Akismet, the excellent comment and trackback spam filtering plugin.
The dashboard page includes most of the statistics that bloggers would be interested in - referrers, top posts, search engine terms, outbound clicks, and incoming links, all laid out in a clean and easy to read format.
One important difference between this plugin and many other stats plugins for WordPress is that the stats aren't stored in your own database. Instead, a snippet of Javascript code collects the necessary information and passes it on to WordPress.com, decreasing the load on your server during high traffic periods. A downside is that you have to login to your WordPress.com dashboard to view the stats; they're not integrated into your hosted WordPress setup's dashboard.
I installed the plugin yesterday and I'm liking it so far. It hasn't slowed down page loading times at all, and the statistics collected are useful and relevant. I'm using it alongside FeedBurner's StandardStats feature, which I've been using for several months and have been pretty happy with. And, of course, I also use AWStats, which ASO enables on all their packages by default. What can I say? I like numbers and pretty graphs. :)