Dwell, the more humble and green-friendly and Moby-ish version of Architectural Digest, has been quietly increasing its circulation and spread since debuting over six years ago. Yesterday, longtime editor-in-chief Allison Arieff abruptly resigned, citing a "fundamental change in the magazine's mission and philosophy." The follow-up press release (with plenty of vacuum-filling promotions in a "staff reorganization") from Dwell president Michela O'Connor Abrams was even more obtuse, hyping the Dwell "brand" (website, conferences, line of prefab homes) rather than the magazine itself. What new fundamental change precipitated Arieff's jump? Hooker ads in the back? Pro-toxic paint advertising? A shift in the fruit bowl policy? Your guesses welcome. At least this will give Arieff more time to properly enjoy San Francisco.