If there's a ball game in the evening, it can screw up the TV program schedule for the rest of the night. I would like the TV guide channel to indicate which shows _will_ definitely appear, but possibly late, and which shows may be canceled completely if the game runs long.
Indicated simply by
an asterisk, or by listing the show in parentheses, respectively.
Useful because:
A. This way you don't have to scroll back in time to see if there was a ball game earlier;
B. TV guide schedules allocate ridiculously small amounts of time for sports events. For example, 2 hours for a basketball game. Please.