I wonder if people will drop Photoshop from their list of deficiencies when the topic Tablet vs. PC comes up. Often, some people bring up the lack of productivity tools like PS, X_Cad, writing and building code etc.
My Photoshop workflow depends on its ability to act as a plugin host for third party workflow tools and to integrate with the rest of a professional toolchain. So, for me, Photoshop functionally remains a PC/Mac application. (This applies to most applications ported to iOS or even the Web with such fanfare -- I still use Office plugins here and there...)
It's wonderful that Reaper has a native Linux version! I might just go with Linux when I have the means to build a dedicated mixing and mastering computer, though I'll miss the ease and quality of SerumFX. Unfortunately, few VST developers have taken advantage of the new Linux support in the VST SDK. And then there's Ableton Live. All of it runs on Windows and Mac. None of it is likely to see an iOS port.
I need my whole workflow to come along. None of it is trivially replaced.