7. It depends on your experience with playing the offline TCG, in my opinion. Though it was far better than I, the "seasoned" player what thought it would be unchallenging, was expecting.
The online tutorials help you learn to play it better than the rulebooks do. (b'-')b
But I still find playing in person more fun, because you can do idle chatter while you play or after you play. ^_^
You might find the online one more fun because it's essentially a video game, though, and you're not competing against other people.
It's not actually fully online person-vs-person play at the moment. They're still developing that feature. You're just playing against a computer player right now in the "Trainer Challenge". It is, after all, still in its beta stage of development.