BioShock comes out today and you play it on a widescreen TV or monitor, you're going to get some cropping at the top and bottom to make it fit the full screen. Folks with regular square displays will get more of the image on screen. A posting on the 
2K Forums shows the differences and this does affect both the 360 and PC version. The lead programmer of 
BioShock in this 
post stated that you'll see more in widescreen though so there's some discrepancy there. Let's hope a patch comes out to fix those that play on their big screen TVs and widescreen monitors. The image below is from the forum post.