Google has just announced the release of Page Speed, a Firefox add-on that works with the Firebug extension to provide developers/webmasters a way to improve the performance of a website with regards to load times and other optimizations.
The add-on makes use of commonly accepted best practices that Google and other websites implement.
There are quite a lot of similarities between Page Speed and YSlow which is a similar add-on created by Yahoo for tracking load times and performance issues.
If you take a look at the screenshot above, you will find it pretty similar to YSlow, however YSlow has recently updated the plugin which saves the uncanny resemblance.
The information provided by Page Speed is nevertheless very useful for optimizing pages and websites and is definitely worth trying out.