i don't think an iphone 4s can outdo anything over my GS2 (rooted with custom ROM).
battery: i get 3-4 days of battery life with light/moderate use. occasional browsing and etc, and the phone will go from 100% to 80% by the end of the day. i am also going to buy a pair of batteries that have more capacity (but same size), which will be beneficial for me when I go camping for 2-3 days (it will be my mp3 player and flashlight at night).
durability: look up videos on the GS2 vs. the IP4S. dropping the IP4S from the waist down will crack your screen. you can drop the galaxy s2 from the shoulder down and still expect your phone to be intact. i don't even use a case on my phone. if iphones are known for their pure beauty, then why does everyone always have to buy cases once they get their phones? and i've even shut my car door on the phone twice and the it's not even close to being broken.
widgets: i love widgets; they are so useful. i have dictionary, wifi/3g switches (which is important to me, since i'm only on 200MB data), news feed, and weather widgets. they all make using my phone more convenient.
value: as far as holding value goes, i find that to be misleading; at least in my experience. i got my GS2 for $0.00, while i would have had to purchased an iphone for $199. in a year from now, i am quite certain that the gs2 will still be worth at least $200. that means i put in $0 and can get a minimum of $200 for the phone, while with the iphone 4s, i would have had to pay $170+tax, and i'd be getting back $400ish for it.
there are certain things that iphones do better than androids, but my opinion is that they are insignificant features.. while androids offer significant features that apple hasn't been able to provide. iphones are better than androids out of the box, but with some work in flashing your ROM and some tinkering, the iphone doesn't compare. i don't get why people don't want to put in the work (or pay someone to flash it for you) to get your phone to offer a gazillion more features. what's the point of having this phone then? to have something that looks shiny and pretty?