This post encouraged me to take a look at Google Webmaster Tools -> Labs -> Site Performance for my site. It says 4.3 seconds average load time, "slower than 63% of all sites", and the graph since November shows tremendous variability, varying between 2-6 seconds. I don't understand where 4.3 seconds comes from (even with an empty cache, it's maybe 1.6 seconds to onLoad), unless they're using some old ISDN line or something. And I don't know where the variability over time is coming from, with a lightly loaded server that hasn't changed much in that time.<p>Is anyone else having similar weirdness with their Site Performance graphs?
<i>"Fewer than 1% of search queries are affected by the site speed signal in our implementation"</i><p>It's pretty clear they're just using this to weed out broken sites that take forever to load. If your visitors aren't already bouncing because of long load times, you probably have nothing to worry about.