from my point of view I think traffic...
I have a bunch of top notch photographers at my disposal and one trip to LA with one of them I could have an entire library of the best content...but for the past month I have been working on building up the traffic to my site and it is a slow painful process
Anyone can hire a good photographer and fly somewhere where there is a bunch of hot girls and take pics....but to manipulate the internet into surfing to your site is a little trickier
both are fun as hell though