One of the things that really struck me about Facebook’s launch of a new location-based service is not that it really, really looks and smells a lot like Foursquare but how it has put the spotlight on the tremendous amount of hype that has surrounded Foursquare and how Silicon Valley does such an amazing job of supporting and fuelling this hype.

For months, the buzz has been Foursquare is going to be the next Twitter. While Foursquare really only had one feature (the ability to check in and broadcast your location), it was only a matter of time before other features were added to make it a lot more useful. Then, it would experience hockey stick-like growth.

Silicon Valley played a key role in pumping the Foursquare story, highlighted by the recent infusion of $20-million of venture capital (less the cash that Foursquare’s founders were strangely allowed to keep for themselves).

The deal was Silicon Valley’s way of propping up the hype even though there were already lots of questions about whether Foursquare could become more than a one-trick pony. And while Foursquare does have two million registers users, the real question to ask is how many of them are active users.

I would hazard to guess there is a lot of people who use the service infrequently or not at all. In my world, Foursquare is nowhere to be seen, and this is a crowd that embraces pretty much everything.

Not to throw stones at Silicon Valley but the reality is it plays multiple roles. There is the financing that comes from the venture capitalists and a huge talent pool to support the ecosystem.

But Silicon Valley is also into the selling and hyping its creations. There’s a giant marketing machine built into Silicon Valley’s DNA that does a terrific job of selling people on dreams and aspirations, including start-ups that may or not be able to attract enough users to become viable.

In many ways, this is a key part of Silicon Valley’s success. It is a place where eternal optimism rules. There is no room for negativity or having small dreams. In Silicon Valley, you aim for the stars even if the rest of the world may not buy into the stories you’re telling.

Foursquare is a perfect example of this ecosystem. It is a jewel that Silicon Valley is desperately hoping will turn into the mother lode.

Unfortunately, Facebook has probably exposed Foursquare for what it is: an interesting start-up that captured the imagination of investors, the media, bloggers and people on the bleeding edge but it will never be able to become anything more than it is right now.