If I am not mistaken, just like the 5s I got last year was unlocked, the iPhone 6/6+ will also just come that way. I didn't have to do anything.
I bought the 5s at the edge price, I verified because I have sims for ATT and T-mobile with active service and put both in and verified that service worked. The only carrier you will not be able to use your iPhone on out of the big 4 is Sprint. But Sprints phones are unlocked as well.
Verizon's CDMA version has all the LTE bands, GSM, UTMS, etc. It just doesn't have TD, if you want that and plan on visiting Japan(only place TD is functioning now) then go buy a sprint iPhone.
Verizon Edge is different though. Essentially with Edge you signed a contract to pay the full Retail price of the phone over a 20-24 month period. This may be the reason your Edge phone came unlocked. Any phone purchased at full retail price should come unlocked. I am still thinking that phones purchased at the "2 year upgrade price" will come locked.