Well it does not matter for me. And I think it does not matter to most of the people either.
Well your comparison is out of the line.
Running on a quad core CPU is a totally different issue, while running on multiple screens isn't.
Some games don't run at all because of hyperthreading issues (If I got the term right) - Which is because of multiple core processors. Whereas the actual game functionality is not an issue with single or multiple screens.
Back in late 2007 when core2 architecture had just launched, practically none of the games supported 2/4 cores and it was frustrating as heck. Nowadays the technology is mainstream so support has been extended and in most cases one needs a multi-core cpu. Same thing goes for widescreens and the 3D glasses and the number of sound channels.
We still see BS; like BioShock2 "supporting" widescreen, with the game owners having to edit the .ini's to fix the FOV bugs. Only way stop themselves from feeling sick whilst playing the game on a widescreen monitor. Yes, it was fixed with a patch..by that time most would have already played and uninstalled the game.
Expect this BS from game devs. All there is to it is money now. No one really gives a damn about the consumer nowadays.
Rush rush rush, and maybe patch later after we get the money.
* Updated game trainers and cheats daily
* Get notified when new cheats are added
* Request which games get new trainers
* Priority support with any problem