I think this moves very much along with current trends in the market place. Sony support on these (and other) forums is so vociferous lately because the PS3 has recently gained a lot of momentum.
However it wasn't so long ago, when the PS3 wasn't doing so hot, that these (and other...) forums were full of "the PS3 is d00med!"
That being said, I think currently the loudest group (IMO) is the PS3 fan, hands down. Which is why I often comment on the 360 forums, to show the box some love. I don't hate the PS3, it just doesn't need any more advocates here.