I'm getting ready to order one myself. It will be my third Apple laptop. I've always done the memory upgrade. I will do it again. The one I have now is 5 years old. The benefit has always been that the computer physically gets worn down and old but you're never left behind. My laptop with runs Adobe Creative Suite almost smoother than my 2 year-old iMac at work. It's able to keep up. I am able to download and update whatever I want.
Also, Mountain Lion seems to be coming with A LOT of applications that run in the background compared to a couple years ago. The computers will constantly try to stay in synch, fetching and pushing. I'm not an expert when it comes to RAM and memory and what consumes how much of what, but the future seems to be all about these always up and running, always ready to use, no time to start programs. It's all about multitasking. This will need more memory. How much? I have no idea.
Also, Mountain Lion seems to be coming with A LOT of applications that run in the background compared to a couple years ago. The computers will constantly try to stay in synch, fetching and pushing. I'm not an expert when it comes to RAM and memory and what consumes how much of what, but the future seems to be all about these always up and running, always ready to use, no time to start programs. It's all about multitasking. This will need more memory. How much? I have no idea.