Ah, definitions again...
This has proven to be a very grey area, because the "Pop" in JPop is naturally a bit misleading. I guess it's a legacy thing.
My current point of view is like this:
JPop is the overall term and JRock is simply a piece of the pie, so to speak.
I still regard JPop as the overall term, because when you ask some on to name some JPop bands or artists, then a person who is into popmusic would name for instance Ayumi Hamasaki. A person who is into rockmusic would come up with something like X-Japan.
Don't forget that rockmusic can also be regarded as popular music( and rightly so).
The Jpop-term is still commonly translated as "Music from Japan", whether it's rock or pop (or dance or any other genre for that matter).
I'd rather see it in a different way though, but that utopian view isn't likely to happen soon. The world still isn't ready to accept JPop as common popmusic which resides among the established artists from the west. Only then can we drop the J's and call the music like it's supposed to be called.
Spread the word, people, spread the word!!
(Hey, i'm back from my vacation again! Let me dramatize a little.

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