The reason Firefox doesn't upgrade itself is this is not a new build of the previous version with enhancements, it's a completely new version of the browser.
The "updates" Firefox normally download include things like bug fixes and security updates, not new functionality. They've always saved that for new versions.
I don't understand this front page business. I've browsed it with the most recent IE, FF3 and FF3.5 and all times it looked perfectly fine.