BioShock has a timeless quality. It's possible to create much prettier and more detailed game worlds now, but Rapture's dour, art deco aesthetic has managed to transcend pixel and polygon counts. So it's exciting that publisher 2K is reissuing the game next month (it'll be free if you already own the game), because that'll theoretically make it look even better.
Judging by the trailer below, it doesn't look hugely different. That's probably because there isn't much room for improvement, unless you're only familiar with the Xbox 360 or PS3 versions.
Whatever the case, the BioShock Collection releases on September 13. If you own BioShock and its sequel already the improved versions will be yours free of charge. As for BioShock: Infinite, that won't be receiving a reissue on PC, on the basis that it's already up to scratch.