[nhebb]

The Average Time on Page trend line should give you the information you need without resorting to this. If you have a call to action or a link to your main site on the blog, I wouldn't go changing the bounce rate metric.

If you have a product and are advertising on AdWords, you can spend a lot of time dialing in your ad phrases. With a blog, you have a free test platform right there! Create a side bar widget that emulates the AdWords look and feel, and start A/B testing your ad text.