It is really tough to answer this question, as human likings differ from person to person. A game which I like most may not be liked by another person.
Eg. I am an Online Poker game freak, but my bf is a Slots freak.
But, if you ask my personal view then I must say that Online Poker is MY GAME.
Reason of my liking of Online Poker:
1. It does not depend upon LUCK alone.
2. Skills are very much important for playing this game.
3. Risk of losing money is not as high as fully LUCK-based games like Slots, Keno, Bingo, Lottery, etc.
Due to this liking on Online Poker, I have also created a Hubpage on Poker Basics. You may have a look http://hubpages.com/games-hobbies/Poker-Basics