i haven't played with my phone much since the 4.0.4 update earlier today, but these are some things that i expect to have updated:
-landscape view for the homescreen (without apex or nova)
-auto brightness that actually works properly
-more customization features
-multitouch! tired of playing asphalt 6 and not having my second finger on the screen register!!
-less lag (not that there's a whole lot to begin with)
-less instances of getting phone calls and having an error message come up on the screen and not knowing who called!
-better overall stability
-apps that i disable STAY disabled (ex. google books and movies!)
-the number of background processes staying set to the limit that i set it to, rather than instantly defaulting to the factory setting!
(my signal disappearing problems have occurred with all LTE i have on vzw's network, so i don't blame samsung for this)
that "update list" that verizon shows on their website doesn't have any problems i've ever encountered, and is hopefully not all encompassing.
obviously, it's a pipedream to expect all of these sensible things to occur, but hopefully most of them are now happening