I think this aircraft originally did have 2 FMS. The ERJs have two similar cockpit configurations, one for single FMS and another for dual FMS.
In the single FMS layout there is a single FMS located on the captain side of the center pedastal-aft. The RMU (radios) in this case are located in the same location as the FMSs are located in a dual FMS set-up.
In the dual FMS setup the FMSs are where you see them in your picture, right next to each other with the RMUs up higher.
So this picture has a dual setup, but with one FMS missing...
Who knows why?? Maybe they're putting in a little flat screen TV for DVD watching....