3G iPhone on EDGE plan?

Does anyone know if it will be possible to get the new iPhone with a cheaper EDGE only plan? Reason I'm asking is that they don't offer 3G in my area and I'd like to avoid paying the extra a month for 3G when I can't even use it. I could buy an older iPhone on eBay or the likes, but I'd like to have the possibility of 3G if they ever get it in my area. Thoughts? Any advice would be greatly appreciated.