@Newdeath: Which is why you have Goku losing to Superman. IIRC: Most role-playing games and AD&D rules have Ki as magic (see Everquest, NeverWinter nights, etc.).
Historically, Ki is magic, they even have a branch called "Ki Magic".
@rpgr: The thing is that magic enables the user to do much more than ki. Magic users are capable of creating objects out of thin air, altering the properties of certain objects and even energy. Hell, even Supreme Kai used "magic" and not ki to create Katchin.
@Newdeath: And creating energy out of nothing is not creating something?
As I said before, western magic = creation of matter or summoning of spirits
Eastern magic = creation of energy or redirection of matter and energy. Taoist magic for instance which uses Ki
Sources with top tier geek creds have deemed ki energy as magic.
Just as necromancy and pyromancy are different schools, ki is just that, a different school.
@rpgr: Creating energy out of nothing is energy projection, an ability in its own right, not affiliated with magic. Magic is the use of supernatural methods to manipulate natural forces and create various effects. Simply projecting energy is something else entirely. Anyway, this topic deals with ki from DBZ which clearly isn't magic since they've been differentiated in the manga itself.
Each character has a specific Ki signature. So it might be that Buu's Ki naturally offers regeneration. And I assume that Ki is used for everything even magic. Otherwise they wouldn't put Babidi in a game and have his magic use up Ki. The same for Buu and his special candy beam.