Suppose I should post an update since this thread has been resurrected from almost a year ago. Through the feedback I got here and some research I came to the same conclusion as many here; that by any meaningful metric they are the same saw. This spring I found a good deal on a 460 and have been very pleased.
One rumor I have heard is that they keep the Jred prices lower while still maintaining the quality by using off-the-shelf components thus almost eliminating engineering and R&D costs. Example is that Husqvarna designs a brand new state of the art widget to go on the Husky saws. Jonsered now inherits the previous generation widget that is proven, in production, and in stock.
One rumor I have heard is that they keep the Jred prices lower while still maintaining the quality by using off-the-shelf components thus almost eliminating engineering and R&D costs. Example is that Husqvarna designs a brand new state of the art widget to go on the Husky saws. Jonsered now inherits the previous generation widget that is proven, in production, and in stock.