Mac OS X screenshot destination
There is no way you can change it. In OS X the screenshots are handled by the OS, unlike in Windows. That’s why they go to the desktop.
You can manually change the screenshot folder for OSX (google can help with that easily), however it will make ALL of your screenshots go into the folder you specify. Not just GW2 screenshots.
So I’m sorry, I can understand that it’s pretty annoying, but it’s a limitation with how OS X handles screenshots, the game can’t specify where to put them.
Actually, my mac os x screenshots go to documents (I changed that via terminal), but my GW 2 screenshots I take ingame go to desktop. SO…
When I take a screenshot, I use the OS version of taking a screenshot rather than the in-game one. [Cmd] + [Shift] + 3
I find it quicker than using the keys the Client uses.
So with that, is there a way to change where the OS screenshot destinations are? I personally prefer them on the desktop so I’ve never looked into changing it, but might be worth a shot looking into. 
Edit: Apologies – I didn’t realise the reply above was by the OP!
(edited by penelopehannibal.8947)
The thing is, I play GW2 in windowed mode (not fullscreen), so taking screenshots by native Mac OS X function [Cmd] + [Shift] + 3 is not the best option, because it captures the whole screen including dock etc..
There is really not a way for ANet developers to choose different GW 2 screenshot destination than desktop?
P.S.: How to change screenshot destination when taking screens by [Cmd] + [Shift] + 3: http://www.idownloadblog.com/2014/06/15/how-to-change-where-screenshots-are-saved-on-mac/
(edited by Dejw.5164)