This was the main reason I was personally against it. Besides the fact that I just never felt the Riddler (much like the Penguin) was ever a true threat to Batman on the scale that TDKR would need, his whole style is just too close to Nolan's Joker for it be really fresh.
Most of the Joker's attacks revolved around some sort of setup, where Batman had to decipher what was happening in a set amount of time before people died. Add to the fact that the Riddler isn't a killer, and it would have been a watered down rehash of things we already got. If the main argument, besides Heath's passing, against the Joker returning is a "more of the same" approach, then I just couldn't understand how people would see the Riddler being all that different, at least from how Nolan established this version of the Clown Prince of Crime.
It's not likely...but what if nolan is just screwing with us, and riddler actually is the villain? I think we'll find out who the villain is through the viral campaign.
He'd be a second rate Joker at best.. and at worst a saw villan.
Something tells me we'll see a "Rise" of a fallen villain from previous films. Don't be shocked if Raas rises from the Lazarus Pit.

Did Nolan say The Riddler wouldn't be in it or that he wouldn't be the villian? the Riddler's motivation is being the smartest, he could be working for the police in tracking Batman.
Did Nolan say The Riddler wouldn't be in it or that he wouldn't be the villian? the Riddler's motivation is being the smartest, he could be working for the police in tracking Batman.
The way Nolan stated it was not Riddler is not THE villain.
Which may mean he is NOT the ONLY villain in the film.
Perhaps Riddler is one of many antogonists?

This is a sincere question but what makes everyone believe strongly that The Riddler will even be used? How do we know Nolan won't go for a lesser known villian this time and make him or her popular on a grand scale?
The Riddler just doesn't seem to work for any epic closing to The Dark Knight's sequel. Pulling strings from behind the curtains of Gotham City, or Zodiac style is boring and overdone. I'd like to make a friendly wager that The Riddler won't even be used, and if he is used, it will be WB wanting Nolan to erase the past idiotic and disgusting performance helmed by Jim Carrey.