A good side-by-side comparison here:
Samsung Galaxy S7 edge vs. Samsung Galaxy S7 - GSMArena.com
The screen size was the driver for me. The Edge also has a larger battery.
These are compelling reasons, and I keep going back and forth. After watching a nauseating number of vids on the edge apps, I doubt I'd use them much. Coming from the (removable) S5 battery from with I get great daily life, the 3000 mAh battery in the S7 would be a step up, let alone 3600 mAH in the Edge. Going over to AT&T to fondle them one more time before I decide; as for waiting for the S8, why do have a feeling Samsung will step on their d*ck again a la the S6 and do something completely stupid, like allow only wireless charging? Hmmm, just a hunch.