I'm not sure why the level of surprise here. One of the many reasons for the new building was to provide more studio space for shows originating from NY whether live or taped. It's not unique.
Out of 30 Rock right now (which will change somewhat at the end of the year with the Versant spin-off) shows include from NBC: Early Today, Today, NBC News Now (most of the day and early evening), Kelly Clarkson, NBC Nightly News, Tonight with Jimmy Fallon, Late Night with Seth Meyers; From WNBC: TINY, News4 at 11, 4, 5, 6, 7 and 11, New York Live; From WNJU: Noticiero 47 Telemundo Primera edición, Noticiero 47 Telemundo al mediodiá, Noticiero 47 Telemundo a la 5:30, 6 and 11; From MSNBC: Way too early, Morning Joe, Ana Cabrera Reports, Chris Jansing Reports, Katie Tur Reports, Deadline White House, The Beat with Ari Melber, All in with Chris Hayes, Last Word with Lawrence O'Donnell and the 11th Hour with Stephanie Ruhle. MSNBC shows originating in DC may still use 30 Rock facilities for live/taped interviews during those shows. This does not include weekly shows like Saturday Night Live and Dateline.