Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Nehalem and, when it becomes affordable, at 64GB SSD boot drive for Apps and OS X. I think that the latter will come sooner than you think.
 
More expandable graphics options

Would be nice to have replacement for 1900xt before its 3rd birthday...

Quite amazing, that when Apple's pro apps rely more and more on GPU, Apple hypes CPU power and does not offer any real upgrade for GPU for years. Pretty same than when cameras are hyped about Mpix's...
 
Three new ATI cores keep showing up since the beginning of the year ... maybe or maybe not a new card. Seems a pair for the notebooks and one other.

Even if Apple didn't offer the ATI Radeon HD 38x0 -- be nice to see a retail one from ATI again that isn't an OEM offering.
 
I want universal access to any third-party graphics card.

Failing that, I was Apple to create a department that does nothing except devote their time to making the biggest and baddest cards available for use in the mac pro.

Besides that I want to see 4Ghz processors and faster bus speeds.

That's more on the graphics card developer than Apple, at least how I understand it. Modern EFI video cards (as opposed to a BIOS video card) will work in a Mac Pro.

The only problem is, Windows hasn't adopted EFI, so graphics cards are built around BIOS. Apple has to call for an EFI version. Thus, choice is limited.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.