Writing this from a cafe in NYC, working through two potential Homebrew investments. Satya and I hypothesize that New York will be an important geography for us so we’re spending quality time leaning in. Why? Already have a bunch of local friends; critical mass of startups in verticals matching our Bottom Up Economy theme; on-the-ground frequently (I grew up here and Satya lived in Manhattan for several years).

My first NYC angel investment was in Charlie O’Donnell, 2007. Had two motivations. First, Charlie is a friend. Second, the round contained a who’s who of city tech. Good way for me to meet some folks who I’d respected from afar. Indeed, I believe that was my introduction to people like Fred Wilson and Scott Heiferman. Company ultimately folded but Charlie put together an amazing team – people like Hilary Mason and Alex Lines. Not just technologists who are good for NYC, but who can hold their own anywhere. Gave me the sense something was brewing.

Thinking back a few years, folks here were starting to puff their chests a bit. Google opened a big office and WC investors began to circle. But talk of NYC tech always lead with whatever company was hot at the time – as if that single comet proved the existence of an industry. Nah, that’s not how it works. You need something more fundamental. Now in 2013 there’s more bedrock.

What excites me most isn’t the Tumblr exit, the recent funding for Foursquare, or anything like that. It’s Roots. A critical mass of NYC startups based in NYC because they should be based in NYC. Bringing technology to financial services, publishing & media, commerce, advertising. Those are New York’s indigenous industries and it makes sense that some of the most exciting companies in these industries are being founded here.

That’s what attracts talent. That’s what attracts investors. The partners are here. The distribution is here. The competitors are here. I’ve been here for three of the past five weeks. One storyline: how quickly the folks shed by Fab are being snatched up by other promising companies. Spent part of my visit closing a very talented hire for our first NYC investment, The Skimm. He had his choice of jobs. Wanted to go somewhere he believed in and experience early stage first hand. The next generation of founders being groomed. Hoping I can write him a check in several years to start his own company. By that time Cornell Tech is throwing off talent too.

If you’re not Silicon Valley, the trick is to look at your indigenous resources and build on top of them. You need a superior answer to why a company should found itself locally. Go NY Go.