The problem is no open source (or even closed) come even close to the Photoshop workflow, and also integration with other monopolized software like Illustrator and Fireworks. It's also one of the reasons why a lot of people can't switch to Linux, winin' it is just not good enough
I've worked professionally with Photoshop and After Effects and access to Adobe software is the only reason I still have a Windows computer. I don't even want to try getting it to work in Wine, and dual-booting just to be able to use them seems like a waste of time.
And until professionals use it in large numbers and are comfortable around it and potential employers want to see it on a resume, other solutions aren't going to matter.
this is a problem imho - why should a vendor specific product be a defacto qualification for a job? I know it is, and plenty of office clerk jobs "require proficiency" in office/word/excel. I say, instead of requiring a product name on your resume, you instead have to show you can achieve a particular effect (say, describe a procedure to achieve a rock texture in the abstract).
I suppose it can matter if that vendor's product is what they use in house and if whatever the other thing is that you know, isn't. They may be worried about the amount of effort they'd need to put into training you to do things their way.
