Yep, it's a touristy touristy place, but it had its charms, like the open roasting pit that greets you on entry. On your table is a little flag, and when it is up it signals to the servers to bring you every type of meat; while I drew the line at chicken gizzards, I did have a bit of an ox testicle, which flavour wise wasn't so bad, but the texture was weird - to be expected really. When you put your flag down, they stop offering you meat.
Last night a bunch of us went to Fogo Gaucho, a Brazilian restaurant that operates a similar way. Noticeable difference: we each had individual little tags that we could flip over to signal if we were ready for more or not.
Final result: Fogo Gaucho wins on quality of meat. The range wasn't as extensive as Carnivore, but the cuts and cooking were much better. Atmosphere wise, Carnivore takes the cake as "The Gauch" (apologies if that means something totally offensive in Portuguese!) is a bit too stiff and formal (though the servers do wear awesome trousers).
Either way, Nairobi is the place for a Meat Fest!