I'm referring to questions in the format of
"What's the name of...?" or
"Which application can...?" where only after the question has been answered you can tag it with the relevant tag, which is basically the answer for the question.
Look at this question, for example: Is there an official name for Metro-Style apps?
It is tagged with windows-8, but not with windows-store-app, which is what the question is really about - because the OP didn't know that what he was referring to is called "Windows Store apps" when he asked this question.
Should this question be tagged with the windows-store-app as well? Is it okay retagging the question now? Should similar questions in this format be retagged as well?