Here’s what we have learned about the departure of the Apple (AAPL) senior vice president Mark Papermaster, the man in charge of the iPhone 4, since the New York Times reported Saturday that he had left the company.

• He did not leave Apple voluntarily. “From what I’ve heard, it’s clear he was sacked,” writes Daring Fireball‘s John Gruber, citing an unnamed source within the company. Insiders had referred to Mark Papermaster, a former IBM (IBM) executive who joined Apple in April 2009, as “the guy responsible for the antenna.” But according to Gruber, Apple does not have a “one mistake and you’re fired” culture — unless the mistake is big enough — and the decision to give the iPhone 4 its controversial external antenna was made long before Papermaster came to Apple.
• He had a “falling out” with Steve Jobs. Citing several unnamed people “familiar with Papermaster’s situation,” the Wall St. Journal reports in Monday’s edition that his departure was “driven by a broader cultural incompatibility… Mr. Papermaster had lost the confidence of Mr. Jobs months ago and hasn’t been part of the decision-making process for some time, these people said.”

“They added that Mr. Papermaster didn’t appear to have the type of creative thinking expected at Apple and wasn’t used to Apple’s corporate culture, where even senior executives are expected to keep on top of the smallest details of their areas of responsibility and often have to handle many tasks directly, as opposed to delegating them… One of these people also said Mr. Papermaster had difficulty maneuvering Apple’s internal politics.”

• The timing of his arrival was unfortunate. “Mr. Papermaster started his position,” the Journal reminds us, “while Mr. Jobs was on sick leave to receive a liver transplant during the first half of 2009. At the time, executives had more autonomy to make decisions, so Mr. Papermaster was likely ill-prepared when Mr. Jobs, who is known for his hands-on management style, returned, said the people familiar with the situation.”

See also:

• The man who made the iPhone 4 is out
• The Papermaster chronicles
• IBM settles; Papermaster to join Apple in April

[Follow Philip Elmer-DeWitt on Twitter @philiped]