As tdd already stated apple releases new iphone/ipods once a year. Iphones are in june/july, and ipods are early September. Thats a full year from now, and unless apple can find a way to fit a camera in and still be able to sell it at the same price points they won't be adding it.
You can use mics with them, however you must plug it in and have it with you at all times - which is a hassle.
Notice there is nowhere for the sound to come out of? so it is much quieter and distorted