In an unprecedented move, Apple updated the GM build for developers yesterday. Not sure of what was fixed, all the issues I faced in the earlier GM build still remain. My advice for the normal OS X user remains the same. Do not upgrade when Mavericks is released, wait for feedback on the overall functionality and not go by Apple’s hype of new features and technology as you might land up with a practically un-usable system, depending on what you use. In short, if you are using a Time Capsule, or, use multiple users on the same system, or, use multiple networks, Mavericks, in it’s current build, would cause pain.