After watching the announcements, reading WWDC reports, and reading many reactions, I pulled together this summary of what we know, don't know, can infer, and can speculate on. And of course, my humble opinion at the end.
The new Mac Pro
Barring any changes,
This is what we know -
1) Size & Shape - 9.9" height x 6.6" diameter, cylinder
2) Case material - polished aluminum
2) Processor - Up to 12 core processing power, Xeon E5 chipset
3) Graphics - Dual GPUs supporting three 4K displays
4) Memory - 4 expansion slots, DDR3 1866 MHz ECC - user upgradeable
5) Storage - 1 x SSD on a PCI Express bus
6) Wireless - Wifi 802.11 ac, Bluetooth 4.0
7) Connections
4 x USB 3 ports
6 x Thunderbolt 2 ports
2 x Gigabit ethernet ports
1 x HDMI port
1 x Standard PC power cord connection
1 x 3.5mm Headphone jack
1 x 3.5 Speaker(?) jack
8) Unified Thermal Core - shared heat dissipation with single large fan
9) Designed and assembled in the US
10) NO internal PCI slots
11) NO other internal storage
12) NO optical drive
This is what we can infer from the images on Apple's website and WWDC reports.
1) Internal power supply (grilled area between the motherboard and the case)
2) Single processor (only 1 set of connectors can be discerned on the motherboard and no room for a second)
3) Interchangeable SSD connector (SSD shown being inserted into the connector)
4) Proprietary video card connectors to the motherboard (no PCI board connectors on the video cards' length and black connector(?) on bottom end)
5) No direct video card display connectors - video outs not connected to GPU cards
6) Apple uses the term GPUs instead of video cards. The "video cards" seen do not function like video cards of old with PCI long edge connectors and video outs on the short edge.
7) The GPU card has the connector for the PCI Express SSD built into it. So, the GPU card could be part GPU and part Storage controller. It would be logical for the GPU to be on the same PCI Express bus as the SSD.
What we currently don't know -
1) Price
2) What is the maximum amount of memory supported in Gigabytes? We can infer 128GB from OS Mavericks.
3) Will there be a dual CPU model? (taller cylinder?)
4) WIll there be a more memory slots model? (taller cylinder?)
5) Will there be another SSD port? (put into the empty space on the second GPU card)
6) Is there a rack mount version?
7) What are the CPU offerings going to be?
Miscellaneous Notes:
Size Comparisons (9.9" height, 6.6" diameter)
1) Micro ATX motherboard (smallest) 6.75" x 6.75"
2) previous Mac Pro Tower - 20.1" height, 8.1" width, 18.7" depth
Questions and Speculation
1) Will Apple make a series of Thunderbolt enclosures to house storage drives and PCI cards?
2) Will there be an upgrade path for GPUs?
3) Is there a new bus for connecting GPUs?
3b) If so, can it be connected externally in the future?
My opinion
The most pressing question is what's it going to cost.
For what it's worth, I'm planning on buying one. Why? Because my 17" MacBook Pro Core2 Duo with which I edit HD videos and render out After Effects projects on is seriously begging for an upgrade. And that also means, I don't have any investments in PCI cards and I'm already used to the workflow of using external storage solutions. I have removable drive bays in those as well as my Blu Ray burner and DVD burner.
Looking forward to more news.