Note that the informaiton below is the summary from Flagship Studios, and more specifically, the Hellgate: London site. Visit the site to view the full notes of the upcoming patch.
Patch 0.6 has one very notable fix – the invisible group member bug has been slain. This was a crafty, fierce thing with rows of nasty sharp teeth, but we believe it has now fallen into the mists of legend. We'll stay vigilant in case it raises its ugly invisible head again.
We've also made great strides on the Engineer Drone issue where items become unequipped. There are some cases where Drones (as well as players), will still have items unequip. The main cause of this is when players "ladder up" the equipment on their Character or Drone by using items with statistic bonuses. This results in the Character or Drone being able to use a better overall set of gear than they normally could, and thus causes issues if the items are not equipped in a specific order (or used at all). We're continuing to work on this one, but it is better with this patch.