HeavenShallBurn said:For me at least the retcon is that they stuck the title Forgotten Realms on it, when it bears no resemblance to the Forgotten Realms.
Retcon means retroactive continuity. In other words, continuity that had been previously established is changed retroactively. No continuity changed with 4e Realms. The landscape changed, but if you have a character travel back in time 100 years, the Realms in the 3e books is what they'd find.
A true retcon is, for example, when they suddenly said Sorcerers had been in the Realms all along, at the beginning of 3e. Or that suddenly dark elves and other such races couldn't see infrared but just could see clearly in the dark. In fact, 3e added a number of retcons because they were trying to avoid a RSE at the time.