User blog comment:Evans0305/IGN's BioShock Infinite article: Creating a Monster + new concept art!/@comment-4295153-20111129013707/@comment-67.180.158.1-20111129083030

That's most likely the case here, that Infinite is a spin-off. As for a BioShock 3, as much as I'd like to see a third, I'm not sure how much more they could do in Rapture. The city's already falling apart in Bio 1. It looks way worse in Bio 2, which is ten years after the first. I think the only way would be to set the events of the third game to take place prior to the events of Bio 1. In other words, make Bio 3 a prequel to Bio 1.