Same hints everyone else has.
Drivers for AMD Tahiti GPUs in 10.7.3, E5 Xeons are
reportedly "in the channel" and that means they will launch any day now. That is the chip Apple would be building a new Mac Pro around, if there is to be one.
There may not be one, and that would be a shame. So let me rephrase:
I would not be shocked if there is on-board 10GbE on the new Mac Pro, assuming Apple is making a new Mac Pro now that the new Xeons are imminent.
At any rate, we'll know well before NAB if there is going to be a new Mac Pro assuming the reports of E5 Xeons in the channel are true.
Best,
Andy