We have photos from a very protective leaker in Taiwan as well as another source of what the component for those cameras looks like.
A dual-camera iPhone would not only be a first for the lineage, but a first in the industry for its implementation: one 12-megapixel unit shoots pictures at a standard focal length while another 12-megapixel camera will go telephoto by up to three times. That could account for the difference in apparent lens sizes you see. Speculation is going about that this technology could be the fruits of Apple’s acquisition of Israel-based LinX.
Moreover, even those pictures aren’t a given until Apple reveals the darn phone. So, settle down and keep both of your cameras — or eyes — open. Patents are pending and patience is packing on for a long ride to September.