Really?! Huh. Thought they were much cheaper than that by now. And LCDs are cheaper than plasma, anyway. Apple wouldn't use plasma.
That's insane. At 15', I can see the pixels on a 70" screen. An 80" would look unimaginably bad. Apple would want to go SHV on an 80", and then the price becomes $29,999.
1, 2, and 3: Not in the slightest.
Look, we're gonna get one. It's gonna be completely redone. And it's gonna be great. But there won't be any FireWire ports, there won't be any optical drives, and there could very well be no internal PCIe expansion. Just a single, double-wide 16x PCIe 3.0 slot for the graphics card. But it will be great.
75% of the existing Mac Pro userbase will whine about it, saying it's the end. The other quarter will immediately buy it and instantly be on the forefront of professional computing across any platform. Half of the 75% will eventually buy it once they see reviews and how well it works where it does, since no other computers from anyone else will be close. A quarter of the 75% will keep their current Mac Pro until it dies, all the while whining on forums about how they refuse to change and how Apple needs to meet their archaic needs. The final quarter will immediately move away from Apple entirely, and half of them will regret it once they see reviews and how poorly the crap from everyone else works.
That's a lot of fractions.