So why are we having any sort of a debate about a 2013 MP? I mean they released a version last year so....
LOL. It is Macrumors... some folks will debate that the sky is blue. They are just anti-everything that is rational.
However, this "speed bump upgrade followed a year, 2011, where they didn't go anything. ( all other workstation vendors in same class didn't do anything either in 2011, but since Apple expectation are more dependent upon actions there is much larger misdirection of expectations. ). Point just last June doesn't establish a norm track record.
It was not a normal upgrade. As a "We have not quit on the Mac Pro" upgrade it was fine. That speed bump gave them a mechanism to talk about whether continuing work or not. Apple said it was.
On the other hand, 2-3 year old GPUs when ( 6000 and 7000 AMD series were possible candidates) also sets negative expectations. Apple only rarely, if ever, skips completely viable GPU upgrades. Similarly, Apple skipped on a completely sensible CPU upgrade also. When Apple shipped the upgraded Mac Pro major competitors were already shipping Xeon E5 alternatives. Again very uncharacteristic of Apple's track record on other Apple products to skip very significant and viable components in an upgrade. Both of these raise expectations that Apple is "asleep at the wheel" when it comes to the Mac Pro.
When Apple failed to get drivers for new GPU cards out in a timely fashion (10.8.3 ) and withdrew the Mac Pro from EU market because still had not worked getting a new model operational. The relatively short warning too for the EU withdrawal is another contributing factor to building "Apple will pull the rug out from under you on short notice" expectations. Again those actions (failures) generate negative expectations. So not only screwed up in 2012, they have continued to screw up in 2013.
So no, the speed bump last June didn't buy a 'we're back on normal cadence' card. By Apple's actions since then, there is little reason to expect a broad range consensus that the Mac Pro is on a normal Apple upgrade track at all. That is exactly why there are many folks still trying to peg to this some Intel part that Apple "had to" wait for. Or just saying that it is dead. Or that it will be butchered into some Mac mini/headless iMac monstrosity.
The speed bump plus the "we will be doing something in 2013" presents reasonable grounds to expect them to come through in 2013. However, Apple is steadily loosing folks who find that creditable.