More optimism for the entrepreneur-turned-venture capitalist with the combination of mobile, cloud and social

Silicon Valley started three years ago this month by longtime business partners Marc Andreessen and Ben Horowitz (first Netscape, then LoudCloud and Opsware). They've since raised $2.7 billion and have backed 150 companies, including newly-public Facebook, Zynga and Groupon, as well as hot private companies such as Pinterest and AirBnb. Earlier this month, Andreessen Horowitz made a $100 million bet on GitHub, a cloud/social play for software engineers to share and store their code.

Speaking in an interview, Ben Horowitz - company's business partner, said that it has been the first time that the company has 3 major high-impact platforms all connecting in the market at the same time -- cloud, mobile and social. The set of opportunities that's coming off of that are really profound.

GitHub has kind of changed the world in two respects: it's cloud and it's oriented around people - so it's a social network. That has some pretty profound effects in terms of network effects increasing returns. If you're building software today, it's only partially the code you write. It's mostly the code you collect, and all that code is in GitHub, and as a result, all code wants to be in GitHub. 

Horowitz also mentioned that there's a lot of good opportunities in both consumer and enterprise. There are over 2 billion people on the Internet. So if you build something they all want, that's a hell of a thing. In the public market, there's no question Groupon and Zynga haven't [done well] and people had higher hopes for them. But they still are at multiple billion dollars and Facebook is well over 60 billion. That used to be a valuable company.