Under Download and install in the Nokia Photo Browser, it says the following:
Devices with Qwerty keyboard:
* Space to rotate the screen
* 'q' to zoom-in, 'w' to zoom-out
* 'a' to left-rotate, 'w' to right-rotate the image file
So 'w' is used both to zoom out and to right-rotate (btw, the terms 'clockwise' and 'counter-clockwise' are a lot more intuitive).
URL: http://betalabs.nokia.com/beta
I don't have a qwerty-phone, so I can't test what keys are actually used...