I finally replaced my useless battery on my 15" MBP this past week. The old battery wasn't even holding a charge any more so rendering it useless as a portable. lol Anyway, new battery arrived, I calibrated it as instructed and I'm definitely noticing that my fan is whirling around a lot more now with the new battery. Is that normal? I don't recall the old battery needing to cool off this much even when it was fresh. I'm afraid my MBP will go up in flames.