Some blogs for Columbia and NYC:

http://www.bwog.net/ - Columbia's blog created by the staff of the Blue and White, Columbia's undergraduate magazine.

http://eater.com/ - about food in NYC

http://gothamist.com/ - about happenings around NYC

http://nyc.metblogs.com/ - blog about stuff going on in New York

http://www.overheardinnewyork.com/ - things overheard around New York

*ADD MORE!!! JUST DOUBLE CLICK TO EDIT*

http://theragblog.blogspot.com - A blog for the Columbia University Community

http://www.cupblog.org/?p=418 - A blog run by Columbia University Press

http://columbialibertarians.blogspot.com

- A blog for Libertarians at Columbia University