Adaptly, an NYC startup that manages advertising campaigns on social networking platforms like Facebook, Twitter and StumbleUpon, has raised a $10.5 million B investment round, led by Valhalla Partners.

Adaptly was cofounded by two youngsters fresh out of Northwestern, Nikhil Sethi, 23, and Garrett Ullom, 22, indicative of the new crop of very young industry entrepreneurs. Payments processing startup Gumroad, which just raised $7 million, was founded by 19-year-old Sahil Lavingia. Incidentally, Instagram was founded by twenty-somethings Kevin Systrom and Mike Krieger – and sold for a billion dollars Facebook. Ullom also dropped out of college, like Lavingia did, which is also indicative of another trend pointing to the irrelevance of a college degree in certain sectors of the tech industry – unless of course you’re Scott Thompson

Adaptly currently has about 50 employees, and Sethi claims a gross revenue of roughly $10 million in 2011, and will “greatly exceed that” in 2012. The startup previously raised $2.7 million, and also brought on Time Warner and Vivi Nevo as new investors.

Adaptly calls itself a “social media ad buying company that is revolutionizing social web advertising by offering agencies a unified buying platform across all social networks. We also help you harness the unique value of each social network in order to increase social engagement.” They are also presently hiring.