From some of the examples linked to in the original post, and with some ideas from the Help Center article on on-topic questions, I tried to cover all the bullet points that Super User is not about. Note that some of the following reasons might overlap with migrating some questions, but my train of thought is that these reasons can be used for questions that could technically get moved, but would likely be closed as off-topic after doing so anyways (since we try to not migrate crap to other sites :).
So, starting with the bullet point(s) the reason was derived from, followed by the reason (+description), some examples, and any other notes if applicable:
- asking for a shopping or product recommendation
Shopping Recommendation (or Software/Hardware Request?)
Questions about specific product recommendations - hardware or software - are off-topic. A general guideline is to ask a question about or regarding a specific issue/problem you face.
suggestions to upgrade my intel celeron laptop
Tool for periodic wifi checks and reconnecting (Windows)
Gaming: Xeon E3-1245 V2 versus i7-3770
I emphasize general since there are interesting/theoretical questions that don't fall under this category and can still be phrased as on-topic for Super User.
- video games or consoles
- electronic devices, media players, cell phones or smart phones, except insofar as they interface with your computer
Not About Computer Hardware/Software
Questions should relate to computer hardware/software and not to electronic devices (such as smartphones, game consoles, or media players) unless dealing with the interfacing of such a device with a computer.
This one is pretty self explanatory, but I don't think we need to have two seperate categories for hardware and software - whichever is in question should be apparent already from the question itself.
- programming and software development
Questions asking/requesting other users to write code are off-topic, and are generally off topic for Stack Overflow as well. Programming-specific questions can be asked on Stack Overflow, however questions regarding the use of development tools are on-topic for Super User.
AHK script to toggle hidden folders in Windows 8?
script to scroll page by cursor movement - add the option to pause and change speed with keystrokes
spreadsheet to calculate weekly increase
I think this one will generally only get used for the coding questions that will end up getting closed on Stack Overflow anyways, but would be good to have (as coding questions to pop up on Super User rather frequently).
- issues specific to corporate IT support and networks
Questions on Super User should deal with consumer-level hardware/software, not those used by large corporations. While some specific questions may be on-topic, questions should (in general) relate to software and hardware available for purchase and use in the residential domain. While these questions are off-topic for Super User, they may be on-topic for Server Fault.
Issue with creating an Windows 2008 Virtualized image with qEmu
Again, this one might get used more like the previous one (questions that might get migrated to Server Fault but don't because they'd get closed there anyways).
And last but not least:
- websites or web services like Facebook, Twitter, and WordPress
Relating To Web Application/Service (SAAS?)
Questions on Super User should deal directly with hardware/software, and not web-based applications or services. While some specific questions may be on-topic, questions should (in general) relate to software and hardware used to host or run the executing environments and not the applications/scripts themselves. While these questions are off-topic for Super User, they may be on-topic for WebApps.SE, or if they are related to programming, Stack Overflow.
Are there any blog posting systems more aesthetically appealing than Wordpress?
JS fiddle (as well as other websites) with tiny text
Largely because we can migrate these questions to WebApps.SE now, this might not be used a lot - but as I mentioned before, I think it may be worth having another off-topic label for those questions which could be migrated (like some of the ones above), but shouldn't be, since they would be closed anyways.