Also more storage space, faster GPU, better battery life and better base RAM.
If Apple phases out the 13" MBP, I'll phase me out of Apple.
The SSD options are the same. The difference in the GPU is negligible (only the base speed is different - the boost speed is the same). They also have the same base RAM. True, the Pro can be upgraded to 8GB, but is that a function of the thickness? I doubt it.
I can see tolerating a larger form factor if you need extra features, but I don't see why there is so much opposition to producing thinner notebooks.
Remember that the Air is the replacement of the MacBook line. There may well still be a Pro/Air split, even perhaps at the 13" level, though less likely since there is a lot of overlap. At the 15" and 17" levels, there may well still be sufficient room for a secondary 2.5" HDD. There definitely will be room for a dedicated GPU in the larger machines, as well, and perhaps even upgradable RAM. The 15" and 17" platforms have much more surface area with which to work. Apple doesn't need to make the same compromises as it does with the 11" or even 13" Airs.
The general trend with computers for decades has been toward faster and smaller designs. The trend largely stagnated for the past 10 years, but seems to have been reignited by the success of the MacBook Air and Intel's Ultrabook concept. I'm not sure why there is so much resistance this time. Heck, if "portables" were still the size of the Mac Portable or even the Powerbook 540c, we could have PCIe expansion slots, 24 hour battery life, 64GB RAM, and the most powerful dedicated GPUs running. Why did we ever go smaller than that size?
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Of course the won't have the same processors. I am also absolutely fine with the trends in power consumption and dynamic clocks. The problem I have is that higher end processors are going to be ignored to fit into these models.
I think you are missing the point of Haswell. The 35W and 45W monsters will be going away at that point. 17W and 25W will be the new mainstream. The 15" and 17" would be perfect candidates for the 25W.
No, but the problem is can they jam those packages in there while maintaining decent temperatures? They haven't done it with the Air as of yet (dedicated graphics).
They haven't done dedicated graphics in the 13" Pro, either. It's a function of the surface area, not the thickness. Again, Ivy Bridge and Haswell bring faster graphics, and it's apparent from Apple's CPU/GPU choices over the past few years that they believe the 13" and smaller models can make do with integrated graphics.
I don't want 90% of what my 15" can do, I want 100% and I want to be able to connect a multitude of devices and upgrade my RAM to 16GB+ (not at Apple prices and on my own terms).
See my post above about the Mac Portable form factor. As for the Air, there are already third party blade SSDs. Let's wait and see about RAM, but I don't see a technical reason why it would need to be soldered into the 15" and 17" logic boards.
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You answered your own question. People bought the 12 inch Powerbooks because they offered things the iBooks at the time didn't.
That's preferring the functionality, not the size. I was replying to a poster who was commenting solely on the size and weight of the 13" Pro vs. the size and weight of the 13" Air.