So let’s see if David Letterman will ease up on John McCain now that the Republican presidential candidate is slated to appear Thursday on The Late Show. I think Dave and his writers are right now making plans to further ridicule the guy. Dave’s been merciless ever since McCain angered Letterman by cancelling at the last minute September 24th, claiming that he was heading to Washington DC to deal with the economic crisis, and then sitting for an interview with Katie Couric instead. (See David Letterman Busts McCain For Lying and Letterman vs McCain, Round 2).

Meanwhile, Barack Obama’s presidential campaign still is waiting to hear whether ABC and Fox will join CBS and NBC in selling him that half-hour block of primetime six days before the election. The Democrat wants a “roadblock” — an airing in the same time period on all four major broadcast networks. Fox needs to wait and see if there’s a Game 6 of the World Series that night. ABC has to decide whether to preempt its beleaguered Pushing Daisies. But the network may smell opportunity knocking (no, not that awful low-rated reality show!). Viewers may want a programming alternative to the Obama time buy. Meanwhile, the Democrat was able to buy the 30 minutes for less than $1 million, which is a pittance compared to what NBC and CBS normally charge from 8PM to 8:30PM. It’s because the campaign will be charged the “lowest unit cost” in compliance with federal law.