True, the reason why I feel its declining other than "the sales are down" stats every year is that a lot of games released on xbox/ps3 dont move over to PC, I heard rumours a few months back that GTA4 was not going to be released on PC(although i know now it is, just later on pc) Also gaming prices are much lower on pc even new releases compare to a new PS3 or Xbox, sign that theres less demand?
GTA games have always come out later on the PC so that one cant be used as backup to claim PC is dieing.
PC games have always cost less than on consoles as they don't have to pay a fee to hardware makers like the console games do so cant be used as backup to claim PC is dieing.
And where have you been the last ten years to not already know this.