An interesting write-up of the contribution by Michael Lopp (senior engineering manager at Apple) at SXSW2008 describes some aspects of Apple design process (by Helen Walters):

"Pixel Perfect Mockups: “it removes all ambiguity.” That might add time up front, but it removes the need to correct mistakes later on.

Apple designers come up with 10 entirely different mock ups of any new feature (...) and give themselves room to design without restriction. Later they whittle that number to three, spend more months on those three and then finally end up with one strong decision.

Paired Design Meetings: Every week, the teams have two meetings. One in which to brainstorm, to forget about constraints and think freely. (...) Then they also hold a production meeting, an entirely separate but equally regular meeting which is the other's antithesis. Here, the designers and engineers are required to nail everything down, to work out how this crazy idea might actually work. This process and organization continues throughout the development of any app.

senior manager outlining what they wanted from any new application: "I want WYSIWYG... I want it to support major browsers... I want it to reflect the spirit of the company." Or, as Lopp put it: "I want a pony!" (...) The solution, he described, is to take the best ideas from the paired design meetings and present those to leadership, who might just decide that some of those ideas are, in fact, their longed-for ponies. In this way, the ponies morph into deliverables. And the C-suite, who are quite reasonable in wanting to know what designers are up to, and absolutely entitled to want to have a say in what's going on, are involved and included. And that helps to ensure that there are no nasty mistakes down the line."

Why do I blog this? curiosity towards organizational/design process per se, especially at Apple. It's generally rare to see this things disclosed.