I like New York a hell of a lot more than the strip mall called Silicon Valley, but New York is nowhere near SV as a startup hub.
First, the VC climate is different and employee option pools are just shitty (5 to 20%). You won't find good engineers willing to work for non-founder equity. The people who work for 0.1% of a mediocre startup are not good and you'll have to hire $200-400/hour freelancers to fix their work after you fire them. (One startup offered me $275/h to fix its Rails app and I've never even used Rails.)
Second, the quality of startups is just not there. Granted, 97% of the startups in the Valley are total garbage as well, because the VCs have no taste or insight, but at least SV has that other 3%. New York doesn't. Most of the founders are people who failed out of finance but managed to snag enough connections (as a consolation prize) to raise VC.
Third, there are startups that luck their way into a few good engineers for a little while, but in NYC, they never keep them. There's a lot of title inflation in NYC (Senior Engineer by 24, Managing Data Scientist by 26) but the people with any ambition leverage their inflated titles into better positions in finance (starting around $300k) or at companies like Google and Facebook.
New York is the place where you use startups to get better Wall Street or Google jobs.
