Not to mention that on the programming end the developer only has two API's (Direct X and Open GL) to work with, and can easily find out what cards support what version of each. And with things like the Steam hardware survey it's not hard to figure out what most of the market is capable of running. Figure out what you want to do with the graphics in the game and target the minimum level and above that let's you do that, or decide how much of the market you're willing to cut out and develop with that in mind.ph0b0s123 said:2 (3 if you have to count Intel) gaming GPU makers, instead of the 5 or 6 previously, each with their own language to talk to their cards.
You could argue that this is still more complicated than developing for consoles, but with consoles you're now dealing with multiple API's if you do a multiplatform title, as well as all of the optimization needed to get games on the 360 and PS3 running at nearly the level that a modern PC can handle. And optimizing for each machine is also going to be completely different.
I agree to some extent that developers exaggerate a bit about how difficult it is to develop for PC. There certainly is more hardware to deal with but the tradeoff is having to know the console hardware inside and out and constantly find ways to squeeze more out of it.