If the sensor had an extra (or different) color filter, I'm
sure the marketing and PR guys would be trumpeting it.

They were for the last 6 months or so in every magazine ad I saw.

Example please, McLeod? I'm genuinely interested. As I mentioned
above, it would be no real surprise - Sony built the sensor, and they
have already used an RGBE sensor on the F828. But no-one seems to be
trumpeting it now on the D2X (inc. Nikon), and the review sites I've
seen don't mention it.