According to NFL.com's transactions page, the Lions have re-signed Cedric Peerman, Jake Nordin, Corey Hilliard, and Zack Follett, the team's remaining exclusive rights free agents. It was confirmed by the team yesterday that exclusive rights free agent DeAngelo Smith was re-signed, but so far there hasn't been any confirmation from the team for the other four.
Even though nothing has been reported on the Lions' website, it is likely that all of the exclusive rights free agents have indeed been re-signed. I say that because Zack Follett confirmed to Pride of Detroit that he did in fact re-sign with the team earlier today (woo real reporting!), so it's probably safe to assume that the others did as well.