Not needed for 14.0a1 Rated 3 out of 5 stars

After 14.0a1, you don't need this add-on.
Open about:config, then modify browser.newtab.url.

This review is for a previous version of the add-on (0.4.3.1-signed). 

Rated 5 out of 5 stars

Works fine with Minefield 4.0b9pre (2010-12-18)

This review is for a previous version of the add-on (0.4.2).