They advertised 10 hours for my (now) last-gen MacBook pro. I can easily do 12 hours. And have. Screen brightness at minimum, using terminal.app. I prefer vim to any graphical editor (haven't tried emacs), and nethack is one of my favorite games ever. That's what I spend my long plane rides doing.

I'd be surprised if that's what happened. I suspect this is just another unrealistic number that's the same proportion of reality as the previous numbers.

That said, when I'm traveling and going for extended battery life (read: trans-atlantic flights) I get pretty close to the rated number by dimming my backlight and shutting off wifi and bluetooth.

Apple reported that they were changing the way they measured/reported battery life with the last MacBook air launch, and explained that it was less favorable, but more realistic.

During transitions like this it would be nice to give both numbers on the new and old machines. This at least gives people some type of comparison point.

While that would be nice for the techie crowd, it would read to the typical user like "we were lying before, sorry about that". Not very feasible.

Well, I do get very close to 8 hours on my 17" MBP (when the cpu is not too stressed). That number will go down if any serious work is done, but light browsing etc. takes it all the way up to 8h.

The key I find with my mid 2010 17 is to manually force intel graphics. Several web browsers and plugins seem to invoke the NVidia discrete chip which sucks power.

http://codykrieger.com/gfxCardStatus is a great tool for this.

Thank you for this reminder.

I'm not sure if they're being more realistic.

The previous MBPs had CPUs with a TDP of 35W. The TDP of the CPUs in the 2011 MBPs are 45W. Battery life seems to have dropped inline with the increase in power envelope.

We should see improved battery life next year with Ivy Bridge, or if there's a mid-year refresh with Sandy Bridge processors with new steppings.

Regardless, I plunked down for a 15" today so I could rid myself of the large brick my workplace saddled with me. They didn't believe me when I said I'd buy my own laptop with my own case. Hell, I meant it.

The increase in TDP mostly has to do with the increased GPU power - I think (speculating) that if you were running the 2010 CPU + the nvidia gpu hot for equivalent performance you'd be seeing at least as high a total power draw.

My 2010 15" MBP (i7, anti-glare upgrade) routinely gets 5-6+ hours on battery -- unless I'm doing something that causes the discrete GPU to kick in. Then, I'm lucky to get two hours.

I think the TDP increase is mostly due to the integrated graphics being moved on to the CPU. Overall platform power usage should be lower than the previous generation.

I can totally vouch for this. My 5,3 MBP only got about 4 hours max when brand new as long as I was running OS X and had the power-saving video mode selected. Running Debian, I usually see around 2 hours if I'm lucky.

Yep. My MBP, which was hte latest verison as of last week, gets about 3-4 hours on battery. Way less than they advertised. In the past they've been pretty reasonable. Not so much any more.