It looks like Samsung is going to try to get even more people buying their handsets, with the next-gen Galaxy S7 to arrive in two different display sizes.
We should see a 5.2- and 5.5-inch Galaxy S7 released, which will arrive as the Galaxy S7 and Galaxy S7 edge. We should also expect the Galaxy S7 edge+ as well as the regular Galaxy S7+ released, too. Samsung could use the 5.2-inch displays on the Galaxy S7 and S7 edge, while the plus models will be the larger 5.5-inch varieties.
Personally, I think this is a good move for Samsung as a 5.2-inch smartphone feels much better in the hand than the larger 5.5-inch smartphone - similar to the Galaxy Note range from Samsung, and even Apple's huge iPhone 6 Plus and 6S Plus smartphones.