The site says various sample devices are floating around with slight differences between them.
What They Have in Common
● 4+ inch display (made by LG on at least one of them)
● No teardrop-shaped devices as were rumored in the lead up to the iPhone 4S. Samples so far have been symmetrical in thickness. Also longer/wider.
● None of the sample devices have the iPhone 4/4S form factor
● None of the devices are final versions
Given that the iPhone 4S production didn't start until late Spring last year, if production is starting now it's likely that the iPhone 5 would be released by summer.
The site notes that this same source correctly indicated that the iPhone 4S would not launch last summer.