I've had my MBP since 2007 and have had zero problems with it. Yesterday I updated from Tiger to Leopard by doing an archived install. Today, while sitting in class and on batter power (at 85% charge), it shut down while web browsing and would not turn back on. I get home and attempt to turn it on again and nothing. I then hooked it up to the power supply and it powered up like normal. I wouldn't think the update would have anything to do with it but it's the only major change to my system I've done and then this starts. Can anyone give me some insight to what might be going on?