Phone will be the same width. So those that want a wider phone, give it a break, it will not happen..... Period.
New iPhone 5s will probably have a fingerprint reader, slightly better camera sensor for the back and front, not a 10 or 12 MP since that does not really amount to an improvement, and maybe a slightly faster processor A6X or even an A7. That will be it.
NFC, faster processor, better battery. Fairly typical of any "S" edition. Same look and feel, just faster and usually one random/major feature addition. 3G-3GS = faster, better battery, video recording. 4-4S = faster, better battery, Siri.