Google Analytics have released a new tracking function that allows you to view page load times. This will give you the ability to truly see which pages load slower/faster than others. It also gives you a sense of how your site and server performs during specific hours of the day or overall.
If you are already running google analytics, you simply need to add this function to your GA code:
_trackPageLoadTime();
To view your website load time stats, goto your profile and drill down to Content > Site Speed section (It may take up to 24 hours to start seeing results.
For more info on this feature, check out Google Analytics' Site Speed Webpage.