I was a PES fanboy until Fifa 09, owning every game from ISS Pro onwards. Then PES went shoddy for a few years, whereas Fifa took massive strides forward, not least with the pro clubs mode. I want to like PES again, I really do. But truth is, I want to play with real players in real kits in real grounds. I want the glitz and the glamour. Gameplay wise there's little between them (of course, they play differently, but they're both decent football games) but Fifa wins because it delivers a package. PES delivers a good game of football and not much else. And if you want to play PES online, you have to have a good book by your side to give you something to so while the game tries to find an opponent.
If PES steps up to the plate again I'll play it, but the brand has lost so much of the UK marketplace that I'll probably end up getting Fifa anyway so I can play against my mates. Sad to say, PES has become the Betamax to Fifa's VHS.