Thing is, the valley has a really lovely concentration of early adopters. While there are lots of early adopters around here too, it's still different.
Like for example, we're making an iPad app. Just because we're from Europe we were a few months behind people from The Valley simply by virtue of the iPad becoming available much later.
No matter how much we try to hide from this fact, the web happens in the valley and "far from the eyes, far from the heart" rings all too true.
If you already have all the pieces for partners, and your user base is dispersed, and you don't need capital for growth, then headquarter somewhere cheaper than the Valley (housing and office space can be half to a third the prices you pay here).
Just look at zappos.com. They moved away from the Valley, partly to be in a customer service hub in Las Vegas, and partly because is was just play cheaper.