Gambling is for games of chance, while one can "beat the house" in prediction markets simply by being more intelligent, informed, and better at forecasting.
At least for the non-random-like bets.
Nah, it is gambling. The "intelligent, informed, and better at forecasting is just an attempt to stroke peoples egos so that they gamble their money.
You can beat the odds if you have insider information tho, so I give you "better informed" in that sense.