Gimp is comparatively terrible at a higher level. 3D, vector, text, smart objects, adjustment layers, ... if you are in any industry that relies on Photoshop beyond basic usage, it's very difficult to be with second string alternatives. This is just how things are in the wild, but I find it baffling that this is still the case after so many years.

It really isn't, not for professional (web) designer work at least. It might be ok for removing a couple of red eyes, but honestly the interface is so clunky it's just a PITA to use.

yeah, Gim ps is best after photoshop you should also check the browser based http://www.toolpic.com Photoshop Online Free