This is perplexing me. My MBP is less than 1 year old (11 months) and it just started having really a short battery life this week. This happened suddenly. Last week I could go several hours. This week the batteries life is sucked out of it in about an hour or less.
I have a 15.4" MBP that I bought new last February. I use it every day for programming and internet. The battery has 121 cycles on it which isn't that many according to Apple. I do have the Apple Care Package and I may be talking to them before the 1 year mark.
I normally run plugged it and only use the battery on rare occasions. I may run on battery a few times a month. This week, while in a meeting at work, I watched the battery die in about an hour. This has never happened before.
I just started a life test battery drain down. I'm timing in 5 minute intervals the battery life remaining while it sits idle running on battery.