I love waking up to this sort of news. This isn't confirmed yet, but thanks to SteamDB we have word that BioShock Infinite looks highly likely that it will see a Linux release.
Pretty exciting, as it's yet another game I've never even touched for not having a Linux version. The Steam reviews are «Overwhelingly Positive», so that's a damn good sign to me.
On SteamDB the «depot» page now has a «Linux Binaries» section, and on the history it states this: Changed Depots 214940/config/oslist: linux 214940/name: Linux Binaries
Considering the original publisher is 2K who don't mind Linux ports, and the Mac port was done by Aspyr Media it certaintly seems likely we will see a Linux port soon!