In Venture-Capital-Funded Internet Land, the secret to success is growth.

Fast, uncontrolled growth. Like cancer on amphetamines. It doesn’t matter if you’re an unreliable dog’s breakfast like MySpace. As long as you attract a few million users FAST then Rupert or someone will buy you for half a billion and you’re set.

Sort out the details later.

As the Web 2.0 bubble inflates, “social media” is the buzz. MySpace, Facebook, Bebo, LinkedIn, OrkutHi5 and a patchwork landscape of competitors already inhabiting an over-populated market.

Today, some keen Kiwis launch iYomu, “social networking for grown ups”. The name comes from “I you me us”, and they’re hoping to capture the 25-55 market put off by the teenage-bedroom aesthetic of MySpace and the perceived complexity of the rest.

Instead, iYomu offers features they hope will appeal to families and friends who don’t want to reveal their entire life — like a gigabyte of secure file storage.

Founders Frances Valintine and David Wolf-Rooney seem to know their stuff. I met them at the beginning of the month and their presentation was low on hype. They responded to criticism. They’d done their research and had a Vision. And they were consciously choosing to focus on people other than the bleeding-edge early adopters.

But that’s precisely why I think iYomu won’t fly.

The later-adopters iYomu is targeting rely on recommendations from geekier friends, who in turn are influenced by A-list bloggers. And they’re already saying there are too many social networking websites. Time to concentrate on two or three and dump the rest.

And then there’s that rapid growth thing.

While MySpace has 200M-plus users and Facebook 30M, iYomu is starting from scratch. Facebook is already starting to work in the Baby Boomer and Gen-X markets. On the weekend I spent a couple of hours on Facebook and already I’ve caught up with some old friends — it felt like time well spent. I’ll have to do that all over again for iYomu.

iYomu is still an empty room — and no-one wants to be first at the party.

Without eager kiddies (iYomu is 18+) and other early adopters, the initial growth spike will be smaller, and the target market is wary of putting their life online — I mean, MySpace is full of pedophiles and terrorists, right?

Sure, they’ve got some toys to play with while you wait, and US$1M prize money up for grabs. But I don’t think that’ll be enough.