Given that there was a service called Jajah, I suppose it was inevitable that someone would come up with a competitor called nonoh whose main point seems to be "We are cheaper than Jajah"! Indeed, if Jajah could run a table like this on their website:
You can pretty much expect that a site like nonoh is going to run the inevitable comparison to Jajah:
The race to the bottom and the commoditization of all phone calls (at $0) continues... who will get to the bottom first? (And what, exactly, will their business plan be?)
Tom Keating has more info about the difference between Nonoh and Jajah.