I was going around the WoWhead Cataclysm site and stumbled upon what seems to be 2 brand new quests (one for each faction it seems).
The Horde quest:
http://cata.wowhead.com/quest=24654
Linked as an objective to this quest is the Silithid Swarmers: blue Scorpids! It sounds like they may indeed still exist under this new fortress, however they're spawned from the quest. If anyone in Beta could check this out that would be awesome. Not sure if these spawned mobs would be tameable, but at least there's some hope!Silithissues
The silithid! They're bugs, <name>. Or something like bugs. They're not natural... and we built a fortress on the equivalent of an anthill.
Take this burning pitch. It'll set the buggers on fire and plug up their burrows at the same time. Be careful when you pour this stuff on there - the silithid will come out in swarms!
Look for silithid mounds around the exterior of Desolation Hold. They look like heaps of sand. Kill anything that crawls out.