It's funny to be called "successful" in Silicon Valley. So often, we think of success as being measured by liquidity events or other markers of worldly success.
The reason I think I'm successful is that I have everything that money can't buy: love, family, friends, health. Yet these are things that we rarely hear about in Silicon Valley (unless you think your Klout score measures your friendship...and if you do, I think you may want to take a vacation).
In fact, I think that success becomes more likely after you realize that money and fame aren't the goal. I was fortunate to realize this shortly after I turned 30.
I think it's pretty clear that I've experienced more worldly "success" since abandoning my frantic efforts to achieve it, and focusing instead on the kinds of things that actually make us happy.
As many philosophers (and now scientists) have noted, "success" doesn't make you happy. Become happy, and you'll improve your chances of "success."
UPDATE: Eric Barker has a good summary of The Happiness Advantage on his blog.
(This post originally appeared as a comment on Adam Rifkin's PandaWhale.com, a very cool online community)