I think it is gonna be shock and awe. Does it have to be? No.
This is what I think will be the big features. I will give some reasons.
4 inch screen. Most evidence points to this and I believe it to be the perfect size.
8MP Camera this is a no brainer.
1080p Recording
A5 again a no brainer.
LTE: everyone says no way. This is the way. Apple built their own LTE chip. With a slightly larger 4 inch phone there is room for their new LTE chip. Why do I believe this? Motorola did it. The Droid Bionic has it's own LTE chip which has allowed the Bionic to be thinner with great battery life. 10 hours on LTE with heavy usage and 15 hours on LTE with moderate usage.
Proof: this is Macrumors I know you want it. A guy got lucky and received a Bionic early. He has been posting reviews on Android Central. So here ya go
Droid Bionic during one of his reviews you will see Battery Usage. He has heavy usage on 4G with 5 hours use and more than 50% battery left.
If motorola can build their own LTE chip and have great battery life. Then why the heck wouldn't Apple? Are they not more innovative? Building their own chip, like motorola, would give more explanation for the delayed release.
If they bring all of these things to the table. There will be shock and awe!