No, I do do not think Blizzard will be stupid enough to try what SOE did. Their EQ for PS2 sucked royally. I suppose those who had never played an MMORPG and only liked console systems would like it...but if you had ever even seen EQ you saw right away it was nothing like real EQ.
WoW is so large and part of the appeal of an MMORPG is the dynamic nature of the game. Things can be changed, added or deleted. On a console, while some of that is possible on certain systems...not sure about PS2, but on an XBox there is a drive (my sports games can get online content such as the latest live rosters, etc)...it is nothing like the broad sweeping changes and additions that can be built into a PC game.
Try adding a new class to a console system. The files cannot simply be replaced like on a PC. Every menu, creation screen, item...everything that has anything to do with that class would have to be added to the console hard drive. What a mess. On a PC, true you have to download the files, but they simply replace the files that are present.
And if they do release one, stay away from it! :-)