With the end date for the Comcast-NBC Universal merger still uncertain, NBC has opted to forgo an executive session at its portion of TV Critics Assn.’s winter press tour. With only a week left before the NBCU day of TCA next Thursday, the company finally released its schedule this morning, and it doesn’t feature a panel with executives, a long-standing TCA tradition. NBC’s new top programmer, Robert Greenblatt, is still expected to make an appearance next Thursday though a low-key and informal one as a spectator as his formal appointment as chairman of NBC Entertainment will likely not happen by then. The other new NBC chairman, Ted Harbert, made a TCA appearance last night at Comcast Entertainment Group’s reception.