You may have been worried that three separate story lines in Resident Evil 6 would mean that you get less "on-time" with your favourite character and a less enjoyable time overall. The game's producer, Yoshiaki Hirabayashi, has revealed that each story – in which you play as Leon, Chris or Wesker's son Jake Muller – will be around 70-80% of the length of Resident Evil 5.
If you take that literally, that means that Resident Evil 6 will be more than double the size of Resident Evil 5, although whether that's just story or if that includes hours of exploration and side missions has yet to be seen. You've also got to keep in mind that there are times in the game when the main characters will cross over and so there will be portions of each story that are the same regardless of who you're playing as.
Resident Evil 6 is going to get mixed reaction from fans, the same way Resident Evil 4 and 5 got mixed reaction. At least nobody can say that Capcom aren't trying to give you a lot of game for your pennies.
Source: Eurogamer