Peter Granat introduced himself Thursday morning as the new chief of Vocus, standing before a packed ballroom at the Gaylord National Resort & Convention Center at National Harbor. Meanwhile, at the Tysons Corner Marriott, the man Granat replaced, Rick Rudman, provided his first public exit interview since leaving the CEO post he’s held for two decades.

The near-simultaneous talks by the outgoing and incoming Vocus CEOs may have been unintentional, but the timing was no coincidence. The Beltsville-based PR and marketing automation company is undergoing a seismic change…