Your examples kind of prove the opposite point, these are not ALL popular apps, they are just popular "toy" apps. You weren't able to give a single example of a popular major application.
There are many web based ERPs and CRMs, some of which are way, way more complex than Photoshop. Given one has access to their algorithms, I don't see why Photoshop would be impossible to implement on top of WebGL. Photoshop UI doesn't have the "native feel" anyway. I think it's just a matter of time until Adobe comes with a 90% feature-complete web-based PS.
I'm sorry I wasn't more clear but I'm not talking just about the UI. It's also being able to give realtime feedback and do hugely CPU consuming tasks, which is essentially the core of Photoshop.
Can you give examples of ERPs or CRMs that are "way, way more complex than Photoshop" though? It would be nice to be able to compare.
By "toy" I don't mean that their purpose is necessarily entertainment, but that the difficulty of building them is not comparable to many popular desktop apps - the list is not representative. Like building a toy plane vs a real plane - the difficulty, not the purpose. Major computer games are not "toy apps" in this sense. Sorry if I was unclear.
