Go back to where every you read this and read it again. Make your decision based of that. If you can't remember where you read that, then there is still an active thread right here on MR about the battery update. You'll find some good info there.
Think about the worst that can happen: the update occurs and your battery stops working. No biggie: Apple has already said they will replace the battery if it does this. Go for it!
Ever since the update, my c2d MBP which used to run pretty well refuses to run on battery power. The battery is fully charged. The minute I unplug the magsafe, the battery idicator switches to battery for a second and then ... the entire machine goes dead.