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Custom SMS sounds, the current ones are annoying or not loud enough.

LED indicator light for email, sms, push notification etc so that when I have the phone on silent at work and I miss the vibrate, I would still see that I got mail...
 
3)Maybe have touch sensitive parts on the front to get to common things (wifi, brightness, bluetooth, and airplane mode) quicker and all together.

Those are just a few things I can think of now.
This mainly. The main thing I miss from jailbreaking is opening SBsettings bt sliding the top bar and turning on/off wifi, 3G, location, etc without closing the app. When that, backgrounding, and a winterboard solution come it'll be perfect software wise.
 
1.) Themes, as mentioned
2.) The ability to remove Apple apps that take up unnecessary room on any page
3.) The ability to turn on or off full screen contact photos. It's really annoying that contact images that weren't create/edited on the phone are small (I know, edit once on the phone but still unnecessary)
4.) Some status screen updates (ie LockInfo)

Pretty much anything that makes me want to jailbreak my phone. ;)
 
*Week view in calendar (my main request)
*Ability to turn off landscape typing.
*More customization (themes, fast add to dictionary, custom SMS sounds, status page, etc.)
 
better battery life
themes
...and all the other good stuff that everyone else mentioned


PLUS ...another way to turn off your phone! I dont know if it's just me but holding down the sleep/wake button to turn off the phone is a MAJORR pet peeve of mine!! ...It feels like the button will eventually sink in to the point where we wont be able to TURN OFF or RESET the phone at all!!
 
Custom sounds in general: Everything should be able to be edited.
Themes as people have stated.
Higher build quality. Returning phones due to this is stupid. As well, a metal back again.
Ability to use phone as storage device w/o using a 3rd party app.
Ability to kill processes from the OS directly.
FLASH (this can be done now, WTF)
Better battery life & user replaceable.

And finally:

Apple providing replacement parts that can be purchased online or at the Apple store. Scratched screen? Replace JUST that. Case is worn, replace it. Bezel nicked, replace it, ETC. Apple would make more money if people could walk in and do that instead of getting an entirely new phone, especially if they sold the items for not too much above cost. More people would end up actually spending the money to replace it. I know I would.
 
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