If you use Google Analytics, Asynchronous Tracking is now available. This is a faster way for pages to send data to the mother ship, and was announced at the end of last year. The GA module for Drupal is working on supporting the new tag, in fact a patch is available if you want to run on the absolute bleeding edge.
We’re happy to announce that the asynchronous tracking tag, which came out of beta last week, is now available in your admin interface when you set up a new profile. This makes it easy for everyone to start off tracking new sites with this very fast, state-of-the-art tag.
Google Analytics Blog: It’s now easy to set up new sites with Asynchronous Tracking