Kimble Young has developed an online website performance monitoring called “Webslug”, inspired by webwait. Webslug conceived as an all encompassing way of testing site performance. It measures load time as the user sees it. The time it takes for a page to load fully from when the request was made.
To perform a testing, you just need to enter your website's / blog address and it's all done in your browser. You can also compare your website's speed against your competitors.
Some good resources on front end performance: