The premise and writing of "My Love From Another Star" is very good, but it lacks the diverse cast and other elements that are necessary for a movie or series to become a global sensation. It basically comes down to the same plot as most love stories: Two unlikely individuals find love. It is not very original.
I would say that the movie has a good chance of becoming a global sensation. I think anything can become a hit these days, and we never know which way society's wind is going to blow from one day to the next. It seems like it's dramatic and romantic enough to make it.
Asian drama and especially Korean drama has become pretty big from a global standpoint. Warner Bros owns Dramafever and there are approximately 3.5 million monthly viewers, not all of the Asian. So it's pretty big business and for the past two years, My Love From the Star has gained a pretty intense following around the world, even displacing popular Chinese dramas with a Chinese audience. I'd call it an international hit.
Global sensations are something rather difficult to come by. While many think that they can toss together a few videos, add in some inappropriately dressed women and somewhat offense material and call it a global sensation, that is not actually how it works. It takes serious effort, hard work, and a mind for good music.