Many believe MacDonald was fired from Saturday Night Live's Weekend Update for constantly making jokes premised on his conclusion that OJ Simpson was guilty of the murders he had been cleared of at his initial trial. (Imagine that. Wacky!) Simpson was friends with an NBC entertainment executive.

When MacDonald returned to NBC for an appearance on one of Conan O'Brien's last Late Night episodes in February, he was scarcely more sparing, impersonating Jay Leno and saying the outgoing Tonight Show host, in moving to a 10 p.m. slot, had "outfoxed... red-headed-rube" O'Brien for prime placement in night-time variety shows. Then he dropped an f-bomb for good measure. (See video here.)

MacDonald stayed true to form on Late Show tonight, starting with a risque reference to euthanasia before making a clearly-out-of-bounds joke involving hard-core narcotics. To his credit, Letterman clearly enjoyed MacDonald's rule-breaking far more than O'Brien, even as he rushed to cover up the narcotics reference with something more palatable.

Then, as always, MacDonald dropped another f-bomb or three, for good measure.

Hopefully someone on cable will give MacDonald a show, because otherwise it may be quite a while before he's on the network airwaves again.

The Late Night host is quoted on his reaction to the news in tomorrow's New York Times. It's at least his third version of the story. Notice the subtle and not so subtle evolution:

1. 'Thrilled'

Seaking on his show after Leno's 10 p.m. slot was announced, O'Brien said, "I've known about this for a while... I am thrilled. I am absolutely thrilled that Jay is staying at NBC. " OK!

2. 'An hour and a half' of deliberation

In his first interview after the Leno announcement, O'Brien told the Times the move was actually a surprise: "I don't think any of us were expecting a Monday through Friday thing for Jay like that... And there was a period where everybody was just trying to figure out: what does this mean? ...After about an hour and a half I just started asking if I was still going to be getting the ‘Tonight Show With Johnny Carson' that I used to watch with my father in my living room in Brookline, Massachusetts."

3. Oh, so now it's an hour and forty five minutes!

In the new Times article, O'Brien basically retold the same story, in slightly different words. But for some reason he added 15 minutes to period of inner turmoil:

The move gave Mr. O'Brien pause for about 'an hour and 45 minutes,' he said. 'The 10 p.m. thing, Monday through Friday, I don't think that was something anybody necessarily saw coming.'

O'Brien isn't the only who has second guessed NBC's thinking. "I feel a little sorry for Conan," one industry source told the Times, echoing much of the chatter from the past three months.

O'Brien's comic friend Norm MacDonald even teased O'Brien on his own show last week, saying Leno got the better of the Late Night host (see clip up top). If O'Brien is owning up to more of his own doubt these days, maybe it's because he's gotten so much outside validation for those feelings.

(Video via Hulu via TVTattle)