It's a regression on an existing feature. Regression = bug.

geon · on July 12, 2012

Did it work with one app per monitor at some point? Otherwise it's not a regression.

Full screen mode lets a single app use all your screen area. That is the feature. That you wish it to work differently does not make it a bug.

It's just a sucky solution for multi monitor setups.

zbowling · on July 13, 2012

Yes, it did. iTunes, Quicktime, Final Cut (the old one)... each had a fullscreen mode that worked on single monitor mode.

geon · on July 13, 2012

Wasn't that a completely diffrent thing, not governed by the OS, but implemented by each app independently and not wit the side-swipe app swiching?