Going by the size I would say Bih Jolokia. Thing is they don't look any where near ripe and may have grown another couple of inches if allowed to ripen on the plant. People are always in a hurry.
The same happens over here with Habanero/Congo-types. Most supermarkets tailor to a large immigrant population from the West Indies/Jamaica, and they'll say they prefer their hot peppers green rather than red. It's also mentioned in one of CARDI's reports on marketing peppers to NY and Miami markets.
ya know, i bought a tray of scotch bonnet peppers with a mix of red, orange(light red) and green and I tried a green and I liked it... no I not trying to sound like Katy Perry.