Offline support for Mozilla
Rod's posted about this mornings session on Mozilla 3 by Robert O’Callahan, of the most notable changes is the inclusion of offline storage using WhatWG.
From what Robert was describing this will bring about just a much a mindset change to web development that we've seen with AJAX and Web 2.0 - thou I fear it'll bring about another wave of browser interoperability problems even more than the current crop of CSS/markup and rendering issues. Will we be entering yet another stage of "designed for FireFox" or "designed for Internet Explorer" again?