Updated with more details: For a second time, Keith Olbermann is leaving ESPN. This time, the Disney-owned networks issued a statement saying it had made a business decision not to renew Olbermann’s contract, which is set to run out the end of this month.

“Keith is a tremendous talent who has consistently done timely, entertaining and thought-provoking work since returning to ESPN,” the network said in its announcement. “While the show’s content was distinctive and extremely high quality, we ultimately made a business decision to move in another direction”

Sources say Olbermann found out he was out at ESPN today when Jim Miller, co-author of the 2011 book Those Guys Have All The Fun: Inside The World Of ESPN, tweeted as Olbermann’s show was wrapping at 5:30 PM ET:

In May, another outspoken ESPN personality, Bill Simmons, also found out via Twitter his ESPN contract talks were kaput. One more and we’ve got a trend. One source told us ESPN also was ambushed by Miller’s tweet, but we don’t think that counts.

But a network source disputes the report that Olbermann was blindsided by today’s ESPN action, saying the ESPN2 host and his agent knew weeks ago the company was headed in this direction. It had been reported last week, by some Reporters Who Cover Sports, that the talks were 95% dead. But, of course, that’s different from 100% dead – ask any coroner.

Some sources describe a day of surprises in which, after the broadcast of Olbermann’s show today, staffers discussed having received emails from HR during the telecast, letting them know about ESPN’s decision. Another source reports that the news ESPN was not renewing Olbermann broke shortly after 5:30 PM ET, adding that ESPN “issued statement at least 30 minutes after that after conferring with” Olbermann’s representative.

Within hours of the news Olbermann was out, a few schools of thought seemed to be emerging. One speculated that ESPN’s “business decision” was another way of saying Olbermann had been jettisoned because the NFL gave ESPN a blah Monday Night Football slate for next season, Olbermann (like Simmons) having spoken extremely critically of the league and its commissioner, Roger Goodell.

Another school of thought emerged, however, in which it was noted ESPN originally planned to sometimes use Olbermann on SportsCenter, among his duties, when the network brought him back two years ago to host the nightly Olbermann on ESPN 2. Network execs clearly changed their mind – he did not appear on that program – and, having made the decision not to use Olbermann on any of its higher-profile shows, decided to end the relationship.

Still another suggested Olbermann’s ratings just weren’t good enough to renew. To that argument: the week of June 15-19, Olbermann’s show — reported to have been ESPN’s first daily studio show to have a luxury car sponsor as its title sponsor, Lexus — averaged 199,000 viewers ages 2+. The show following his, anchored by Colin Cowherd, averaged 81K at 5:30 PM in that same week.

“We wish Keith nothing but the best and trust that his skill and ability will lead him to another promising endeavor,” ESPN also said in today’s announcement.

Speaking of Twitter: Today’s news seems to confirm, as we suspected, that when ESPN PR tweeted recently “Keith Olbermann has never been told any topic of his is off limits for his commentary nor has continuation of it been part of any conversation about his future at the company,” it’s because the network already had decided continuation of commentary at ESPN would not be part of Olbermann’s future. The tweet was more widely interpreted as a shoot-down of a THR report Olbermann had been told he could not do commentary in any new contract with the network.

This will be Olbermann’s second exit from ESPN, having previously worked for the network in the 1990s, anchoring SportsCenter. He left to move to MSNBC.