I found (through slashdot) an interesting article about Gimp on Mac and Photoshop. Here are the links:
What I found interesting is the user perspective about software. I like the clear distinction between good and bad software, and open source or not! I believe that we should always pay attention to these two dimensions of the problem: crap software can be sold or downloaded for free, besides, great software can be bought without shame or downloaded. At the end of the day, the point is that the cost you pay for getting your job done should be the minimum possible!