mine is dead too. time for a new batt.

 

I've got the previous model MBP as well -- 2.5 years old. Took mine in yesterday because it went from seriously depleted performance, to the computer shutting down without warning (i.e. majority batter life left). Turns out my battery is toast (something like 500 cycles). New battery is $129. Dragging my feet about replacement, probably do it in a month or so. Most of the time I'm plugged in.

 

As a general note for keeping your battery happy, you should calibrate it per the instructions I posted earlier once a month, and it's a good habit to unplug while it sleeps. You want to keep juice moving into or out of the battery with a degree of regularity.

I've had batteries survive nearly 1000 cycles unplugging at night and calibrating monthly.

 

It needed a new battery, they replaced it for free. And I was not leaving it plugged in all day. But it was draining really fast. Like maybe an hour or less on a full charge, at about half brightness and a mixture of music editing and photoshop/illustrator work. But I'm good now with the new batt.