Don't think so. The CRJ-700 and CRJ-900 are definitely similar enough to be the same article (same engines, same wing) and are really no different than, say, a Boeing 737-700 and -800, or an A319 and A320, which are simply discussed as variants to a main article. The CRJ-1000 is a bigger change, but BA markets them as a family, and until the CRJ-1000 has sufficient market penetration of its own it might as well stay here i think.