Five of the top six spots on Xbox Live Arcade aren't just Japanese; they are all ports of classic titles. When we asked Microsoft Games Studios VP Phil Spencer about the observation, he said he could challenge the assumption that ports and existing IPs dominate sales on the platform. His ammunition was Limbo, the superb platformer that kicked off this year's Summer of Arcade.

"Our number one Summer of Arcade game is Limbo," Spencer said, "by a long stretch." Other games in the five-week lineup included updates of classic titles like Hydro Thunder and existing - and highly visible - IPs like Castlevania and Lara Croft. "I think there was a time when Live Arcade was about IP that people knew," Spencer acknowledged, while conceding that those games are "always going to be important."

"It's changing though," he said. "I really think coming out of Braid, Shadow Complex, Limbo [...] that it's changing a little bit. We see that in the market, that it's becoming less about iconic IP that people know and it's becoming more diverse." And that's a good thing for everyone involved, including Spencer. "I love Limbo. I think Limbo's probably my game of the year right now." Us too.