At this point, there is no indication that there is any kind of battery life bug in ML, and the "large numbers" of reports you may have seen are a very tiny fraction of the total number of Mac users. Your issues may be caused by an aging battery, an SMC problem, third-party software that is not fully compatible with Mountain Lion, something that got corrupt in the process of upgrading or something else entirely.
Try the following:
1) Check your battery status. Choose About This Mac from the Apple menu, click More Info, then click System Report, then select Power. What does it say under Battery Information?
2) Reset the SMC.
4) Try reinstalling the system.
Here is the current info on my battery. It shows not fully charged since it is connected to power at the moment. Please advise if the other info appears normal or not. Thanks for your help.
Pack Lot Code: 0
PCB Lot Code: 0
Firmware Version: 406
Hardware Revision: 2
Cell Revision: 158
Charge Remaining (mAh): 5212
Fully Charged: No
Full Charge Capacity (mAh): 6323
Cycle Count: 360
Battery Installed: Yes
Amperage (mA): -1224
Voltage (mV): 11907
Doesn't look like anything wrong with the battery. You shouldn't get much reduction in battery life at 360 cycles, unless the battery is also getting very old (as in, around 5 years or more).
BTW, note that I'm using a mid-2010 MacBook Pro with Mountain Lion and have been using it for about an hour and a half on battery right now. Here's what my battery indicator shows:
I am on an early 2011 MBP so, yes, the battery should be good but you never know. And thanks for looking at the battery stats. They looked good to me but wanted confirmation. Just went through the SMC process and letting the laptop charge up. Will disconnect power when I get back to 100% and see what happens next. Thanks again.
I got a macbook pro mid 2012 release, I got it about 2 weeks ago... I had about 4 hours of battery life on average when I was using it, doing my regular things I usually do on my macbook... I found out I can install the 10.8 OS for free if I claim it on apple.com, so I did and installed it.
I got it and a few days later i noticed that my battery only lasts 2 hours on average when I'm doing the normal things I usually do on my Macbook pro... Its running 10.8.2 but there has DEFINITELY been a significant reduce in battery life, to around half of what it was...
I have also been installing other apps and things, but only stuff from the app store, so idk if its that, I'm pretty sure its the OS.