Got a new MacBook Pro a few weeks ago which of course shipped with Snow Leopard, so the day Lion came out I jumped the gun and got my free upgrade and installed it. However, since then the battery life wasn't as good as Snow Leopard's, so I decided to try my hand at a clean install even though I'd have to reinstall all of my apps. What a difference it makes to do a clean install! My battery time estimates are back on par with my Snow Leopard's. If any of you are hesitant about doing a clean install, well, don't be!