Take a look at what TUAW said about this update, CRAP!!

[gigi11192]

In addition to these major updates, the MacBook Pro has seen some minor enhancements, too: the entire lineup has dropped in weight, and all models feature a slightly larger trackpad than before, and they include a 'FaceTime HD' camera versus the iSight of previous models.
http://www.tuaw.com/

take a comparison between the 13'' from 2010, see what the heck the changing.
http://support.apple.com/kb/SP583
Size and weight
Height:
0.95 inch (2.41 cm)
Width:
12.78 inches (32.5 cm)
Depth:
8.94 inches (22.7 cm)
Weight:
4.5 pounds (2.04 kg)
Up to 10 hours wireless productivity

exactly the same with the updated one. but the battery dropped from 10 to 7. I dont know what is happening?
let us look from another angle, the 15'' 17'' can have up to 7 hrs battery, why does the smaller 13'' have the same number? It always has at least 2 more hrs to go, what happened this year?

What on earth does the pro line turn lighter and where does the larger trackpad come from?? and poorer battery life.

I have no idea. anyone can educate me on that, please>?

 

[SidewaysTakumi]

The new battery life rating is from newer, more intensive tests.

The old test over-estimated the battery life...these are more accurate.

There are more threads on this.

 

[Steve1496]

They put 7 hours on every single Mac laptop--even the MacBook (which wasn't updated). It's a case of Apple trying to protect itself. They may have been over promising and under delivering--now they will be under promising and over delivering!

The batteries are the same. You'll still get similar battery life to the previous gen.

Steve

 

[SidewaysTakumi]

Check this thread...people talk about it

https://forums.macrumors.com/threads/1101748/

 

[tjb1]

Wow, there needs to be a freakin sticky on the battery life already...

 

[DeepBlade]

From my understanding, it's as simple as.... Core2Duo uses much less battery than i3/i5/i7s........ Even in the last generation, 13" MBPs used Core2Duo and had 10 hour battery life, but 15"/17" MBPs used i5/i7 and only have 8-9 hours battery life.....

Now, this generation comes, and the Sandy Bridge processors are even more powerful (and thus require even more battery than the prev i5/i7s)...... therefore, less battery life.

 

[Steve1496]

From my understanding, it's as simple as.... Core2Duo uses much less battery than i3/i5/i7s........ Even in the last generation, 13" MBPs used Core2Duo and had 10 hour battery life, but 15"/17" MBPs used i5/i7 and only have 8-9 hours battery life.....

Now, this generation comes, and the Sandy Bridge processors are even more powerful (and thus require even more battery than the prev i5/i7s)...... therefore, less battery life.

Not exactly. The 13" White MacBook has been cut to 7 hours too, and that remains unchanged.

 

[SidewaysTakumi]

From my understanding, it's as simple as.... Core2Duo uses much less battery than i3/i5/i7s........ Even in the last generation, 13" MBPs used Core2Duo and had 10 hour battery life, but 15"/17" MBPs used i5/i7 and only have 8-9 hours battery life.....

Now, this generation comes, and the Sandy Bridge processors are even more powerful (and thus require even more battery than the prev i5/i7s)...... therefore, less battery life.

Like Steve said...that is not true. The change is in the battery testing procedures.

 

[Hellhammer]

From my understanding, it's as simple as.... Core2Duo uses much less battery than i3/i5/i7s........ Even in the last generation, 13" MBPs used Core2Duo and had 10 hour battery life, but 15"/17" MBPs used i5/i7 and only have 8-9 hours battery life.....

Now, this generation comes, and the Sandy Bridge processors are even more powerful (and thus require even more battery than the prev i5/i7s)...... therefore, less battery life.

Sandy Bridge CPUs are much more power efficient that C2Ds. Performance does not imply higher power draw, otherwise the battery would go down with every update. Things like manufacturing process (45nm vs 32nm) and microarchitecture affect the battery life and performance as well.

Like said above, the new statement is just more accurate.