Its Konami dude, they've done the math. The fact that they aren't bringing it to Vita is just as negative about the state of PES as a franchise as it is about the Vita. EA sees a market for FIFA on the handheld, but Konami isn't willing to compete with the guys who've been eating their lunch the last several years.
By the simple mathematics of it Konami knows that:
1. they're already losing out to FIFA worldwide.
2. The Vita is the only system where they can double dip with zero extra effort, via a PSP release.
3. Konami as a company doesn't really have the assets to throw behind yet another version of the franchise that would only be viable to a small user base that already has FIFA in their hands, and an alternative path to get a PES title on the system if they're real die hards.
Does it suck for PES fans? Sure. But it says nothing particularly negative about the Vita or Konami's view of it. When/if they cancel the MGS or ZOE collection ports to Vita we'll have something different to talk about. This is just Konami trying to pick and choose how to most effectively spend money in the losing battle versus EA's extremely well funded juggernaut.
Not sure if that holds much water, to be honest. PES has never competed with FIFA sales wise even when it was good, on any platform, and has been destroyed year on year across the board by FIFA during this generation.
Not just that, but Konami have had no problem supporting the 3DS with a bespoke version of the game. PES11 sold incredibly modestly on 3DS at launch but Konami still green-lit PES12, to go up against a FIFA game, after modest sales of their last game, on a system that will still selling badly when that decision will have been made. And after equally underwhelming sales of PES12 on 3DS, they've just announced they're doing another one. Which will probably go against FIFA in another market once again.
Just seems like excuses to me. We hear all this about how easy the Vita is to port to and yet its ignored even for games like this, where its literally the ONLY system people still play that isn't getting the game. Even an up-rezzed PS2, 3DS or PSP port would be suffecient, in my opinion. Better gameplay than the console versions (still) and the Vita screen would do it plenty of favours.
Its not like Konami is afraid of producing different versions of the game, either. If you take into account HD graphics, pointer controls, previous gen visuals, 3D and touch screen controls, Konami produce five different versions of the game year on year, with many different graphics and gameplay standards between them. And not all of them sell huge amounts on the platforms they're on.
The fact they're not even bothering with a low effort, low risk port doesn't look good to me. Be interesting to see whether or not this becomes a trend. Right now it certainly doesn't help stop speculation about third party support on Vita.