We really don't have anything but rumors, but everything going around points to it not being a traditional character meal. As Disney has officially announced nothing but has let a few things "leak" unofficially, there's no way to really tell, but you should be prepared for there being no costumed characters.
There's also stories that although the animatronic Lumiere is pictured in the artist's rendition of the restaurant, it is not being constructed for the restaurant, but for a separate show or attraction. Time will tell as to which rumors pan out.