Chicago-based interactive agency Quantum Leap Communications for the first time ventures into TV when it breaks commercials this week for MSNBC.com. Quantum, the agency of record for MSNBC.com, also will produce online and print ads for the news Web site. The campaign budget was not disclosed. This spot pokes fun at the kind of news exchanged over office water coolers. The tag: "MSNBC.com. Get the day's most important news while you're at work."