There were some rumors in the last few days about the possible launch of the iPhone 5S and even the iPhone 6 later this year, but there is no way of knowing for sure what Apple has in mind. Judging from the previous experiences, it is very much possible that the new iPhone 5S (or whatever they choose to name it) will be released later this year, but the possibility of launch of two different iPhones in the same year is low.
Even if Misek’s predictions regarding Apple’s moves on the mobile market aren’t flawless, he actually predicted correctly about the iPhone arriving on Sprint and T-Mobile, back in 2011, so all bets are on. Quoting from his report :
“We think in- cell is having difficulty ramping to 4.8”, which is making Apple look at switching to on-cell (a different integrated touchscreen technology) and OLED (despite Apple’s suppliers being well behind Samsung in their OLED capabilities) or IGZO.”