don't know if it´s a bug or intended but when you have a character choosen and hower over a weapon in your inventory, you get the tooltip from that weapon and the one you have equiped, so you easily can compare. However, when you have the party inventory up, you don´t get the tiooltip from your equiped weapon up if you hower over a weapon in some one elses inventory.
The same goes for when at the trader. If you open the trade window with character A, and then select character B in the party frame and point at a weapon in the trades inventory, you still get the information for character A instead of character B. The only thing that changes in the tooltip is the cost of the item.
Maby this is as intended but as far as I remember it wasn´t like this in previous patches.
