As far as I know, Siri, and AirPlay mirroring.
Other tid bits include face recognition in the camera app, 1080p video record, and probably some pretty graphics as games that take advantage of A5 come out.
Other than that, I don't see anything else.
I was really just looking for the software (iOS5) differences. I know about Siri and AirPlay Mirroring. Anything else?
Anything that will work on a 4, but not a 3GS? Or the Touch?
MotionMan
A few things like photo editing, tabbed browsing, ect.
http://9to5mac.com/2011/06/07/ios-5-on-iphone-3gs-whats-missing/
(old but provides some insight.)
When you say face recognition are you talking about iPhoto style face recognition tagging or the app adjusting exposure with people win the frame?
AWB? I can't find what browser you are talking about.I wonder why there's no tabbed browsing. I've been using tabs via Atomic Web Browser for quite awhile now. No matter, I won't use Safari anyway... I like the ad blocking in AWB (other browsers have it too). AWB also has a full-screen mode, which is helpful when you only have a 3.5" screen to begin with.
A few things like photo editing, tabbed browsing, ect.
http://9to5mac.com/2011/06/07/ios-5-on-iphone-3gs-whats-missing/
(old but provides some insight.)
Yeah. Tabbed browsing is really an iPad-only feature. Another iPad-only feature that I noticed was that dictionary on website doesn't require Reader Mode, but on iPhone, it does require Reader Mode.
On iPad, tabbed browsing helps you keep track of multiple web pages and switch between them with ease.