In my last few months of Guild Wars, having completed God Walking Amongst Mere Mortals, pretty much the only reason I would log into the game would be to hit B and watch the monthly GvG championships. It was like a game-within-a-game, drastically different to the PvE game, infinitely complex and with it's own tropes, trends and memes, controversies, heroes and villains.
Watching the pros go about their business each month taught me how to do da PvPs: I never played GvG myself, but I used the skills I saw the top players using whenever I entered Random arenas, alliance battles or hero battles, and I think I was better for it.
I'm hoping that the introduction of observation mode in GW2 will allow me to absorb some of the new skills which have been incubating in the sPvP community since launch. I can imagine that there are countless nuances of the genre which just haven't made it out of the community which surrounds it simply because n00bs like myself haven't been able to hit B and stick our noses in to watch how it's done.