If Microsoft Surface does become a popular household item one day -- or even just a hotel lobby passtime -- there will certainly be games for it. I don't believe it will greatly change device interaction in general (not person-device interaction, anyway; inter-device interaction, yes), but its unique interface definitely invites fresh types of gameplay.
Touchscreen technology has been around a while now. The iPhone and Nintendo DS are popular, but all such products require one hand to hold and one hand to operate. MS Surface, being a table, invites use of both hands. That drastically affects gameplay potential.
You might immediately think of arcade-style games when imagining Surface games. But deep AAA action adventure games are also possible... especially if linked to a pair of gaming goggles (3-D films and games should be common by the time Surface comes down in price, so using 3-D goggles might be common).
For example, imagine a game involving free-diving and swimming in the ocean. The player could move her hands on the MS Surface similar to true swimming motions. Starting one's hands in the middle of the screen and dragging them outward would propel the character forward in the water. Dragging both hands to the left or right would turn the character. Dragging both hands up or down would send the character to deeper or shallower water. Meanwhile, the goggles would allow the player to look independently of her movement... which enables gameplay like chasing and fleeing.
Placing the fingertips of one's open hand on the Surface and dragging them together would enable you to grab objects (including ladders). The opposite could drop or throw items, depending on the quickness of the movement. Dragging one hand could also throw objects, since only both hands together move the character through the water.
A light slap of the hand on the table could signal a punch or other blow (though I'm not sure how resilient Microsoft's table is). Dragging a finger in a circle around an object could throw a net.
Anyway, I'm really not trying to design a game here. I just mean to show that being able to interact with a touchscreen using both hands creates many possibilities not available when using only one hand. I don't forsee MS Surface becoming an ubiquitous device anytime soon. But if such a day comes, it could be fun for gamers.