Khisanth the Ancient
Explorer
Actually, according to Echohawk's Complete D&D Monster Index, as of the end of 2008 there were just over 34,000 monsters published for D&D across all of the editions. Note that this includes, however, PC races and different editions of the same monsters.
Still, even with some overlap, that's a heck of a lot more than 5,000. And take into account third-party contributions (and it being over a year later) it probably hits the 50,000 mark easy.
So that's *not* including 3rd party monsters in the 34000? Wow.