During the football scene featuring the Gotham Rogues – the R in the ROGUES fan made sign is the same style as the R in the Robin Comic book – compare both here.
Earlier I speculated (and hoped) that Joseph Gordon Levitt may be playing Grayson but in his Nightwing identity. The actor is listed as playing police office John Blake in the cast list. Speculation that Bane will break or kill Batman in the final film is rampant. What if the “breaking” happens mid film and inspires others to take over for the Dark Knight meaning we might see many cameos from the Batman family supporting cast like Grayson, Tim Drake or Jason Todd?