Of course Photoshop is incredibly expensive so I can see a market for a <$100 app.
- type rendering looks nothing like any browser or OS (as described in the article)
- subpixel rendering makes drawing shapes and lines with clean edges a chore.
- direct selection tool is difficult to use and therefore makes the layer palette the primary means of selecting layers, which becomes tedious with large files
- no support for multi-page documents
- positioning and resizing objects at a pixel-level is difficult
- slicing and image export system is kludgy
- no support for symbols
- objects with rounded corners are a pain
Do you use Photoshop for 5+ hours a day designing web layouts? I'd imagine you'd have a hard time going back to Photoshop after using an application that is better suited for interactive design. I actually started using Fireworks a couple years ago, and while I pretty much hate it, I will never again use Photoshop to design a website.
It was a company practice at my first job — didn't have much choice.
I've always found Illustrator to be equally bad for web, though. It's a vector tool, but the web is still a pixel medium.
For me: Photoshop for manipulating photos, Illustrator for illustration, Fireworks for web/application layouts (although it can handle some basic photo editing and illustrating, which makes it even better for layouts).