This was JUST brought to my attention from a friend on Google+. +Benjamin Roethig of GeekBeat.tv shared with me a link from MoviePilot.com that William Fichtner will NOT infact be the Shredder in the new TMNT film!
From what MoviePilot.com is speculating is that William Fichtner is playing Eric Sachs (obviously already), who supplies the real Shredder and his Foot Clan with the armor and weapons they need. Sachs is merely a power hungry business man.
The above image is actually a brightened image still from the trailer when Sachs is talking to an individual shrouded in shadow.
Now, considering how the individual looks, it would possibly tie into much of the history of Oroku Saki being scarred. In the original Eastman and Laird Mirage Studios TMNT material, Oroku was scarred by a pre-mutated Splinter when Oroku and Hamato Yoshi fought over the love of a woman. In the new TMNT cartoon from Nickelodeon, Oroku was scarred from a fire when Hamato (Pre-mutated Splinter) fought over the love of a woman...Hamato Yoshi's wife.
Based on the scarring, this looks like it may be using the new CG cartoon origin of a burned Oroku Saki.
Considering everything going on with rumors, and rejected ideas and scripts since the announcement of the new film coming August 8th, Michael Bay has been keeping everyone on their toes. Nathan and I have both discussed our theory that Bay has been intentionally misleading everyone on this film regarding that the franchise may infact be more true to the various materials than we originally thought.