I never really believed the Warrior Tank QQ until I seen GC's posts myself, I'm a Palatank and all, but I feel for you guys, GC and his team are being pretty ignorant here, ignoring the most popular tank class to give the other 3 a boost.
My only guess as to why they are doing this, is so the future of the game isn't always dominated by Warrior Tanks, people will role and play DKs, Druids and Paladins because Warriors in WoTLK were not as great as they were for vanilla and TBC.
Don't worry guys! They'll probably start treating us all equally in Cataclysm after they've forced their point upon us.
As for the shortage issue, the problem is, most tanks and healers are in guilds and are raiding. There aren't too many floating about for pugs since they are the two class-roles which get geared up faster and have no reason to go back and do heroics. The shortage issue is afterall with pugs, and not with recruitment; for when I played my crappy warlock in TBC, it was a nightmare finding a tank/healer for MGT HC, or any HC for that matter, hence my re-roling to Tankadin.