I need to be able to burn a master of my new CD/DVD on a regular basis.
If you *really* need to still burn stuff in this decade, a $50 external burner will do just that for you!
I need to be able to slap in a new hard drive as I need it - daisy chaining half a dozen external drives with power supplies and Kensington locks for all of them is a ridiculous option.
I must say this "slapping in new hard drives" is very unusual and probably not anywhere near typical usage (even for "pro" users, whatever that means). Most offices have central storage anyway, especially for bulk storage, heck even at common peoples homes a NAS is quite common.
I'd say that there are two main goals with storage development today:
Speed (for your OS, your applications, and the work-data you are currently working on)
OR Size (bulkstorage and archiving). You easily spot this fact when browsing the offerings of any on-line computer store; they have very fast but capacity limited SSD's for the first requirement, and they also have very high storage capacity but very slow (in comparison) HDD's for the second requirement.
This Apple machine embrace and adopts these extremes to the fullest. People today use SSD disks in their standard SATA controllers to gain speed, but the SATA standard in itself is a limiting factor, so this new Mac uses a PCIe based SSD controller that provides a storage that is 2.5x as fast as normal SSD's and up to 10x as fast as those old and traditional HDD's.
HDD's has never been cheaper per Byte, their storage capacity is enormous, but they are very slow to the alternatives so they are best used for cheap bulk storage of massive data, archiving purposes, or backups. Frankly, I see no reason to have that inside a computer case, not when the various possible external interfaces are so fast as they are today, not when the amount of HDD's *outside* the computer case is virtually unlimited.
I need to be able to double my RAM
That may be so, but I think it's a bit odd. I have never ever had the need to double my RAM. Maybe it's because I bought enough in the first place, I don't know? Whenever I have bought new RAM (every 4 years or so), a new motherboard, CPU, GFX card, etc came with it!
I don't know how much RAM this machine will have, but I'm sure it will be enough for 12 cores to play with.
or swap in a new graphics card when I realize I need a little more performance
OK, many PC gamers who puts an honor in boasting about FPS numbers and test scores etc switches GFX card from time to time. But I think few others bothers. I know lots of Mac people and I have never heard it would be a frequent thing in the Mac community to change GFX cards on a particularly regular basis. Especially not among the "pro" people. They buy a Mac, they use it for a few years until its specs are falling behind or it breaks, then they buy another one. And something tells me this "GFX card" (or rather: dual ones) will offer top-notch performance, enough for every potential Mac Pro customer out there.
but don't have the budget
Ah, but something tells me this computer will be mostly for people *with* a budget!
A custom design in its truest sense, highest performance components everywhere, Apple brand, and it's even assembled in the US (not in China). It won't be cheap, it won't be for people "buying a cheap GFX card now with an ambition to upgrade it later to the one they *really* wanted". Mac customers in general don't work like that!
