Finding good tanks is the hardest part. There are plenty of mediocre tanks out there though. I've run a few dozen flashpoints on the way to 50 and found one that was good. Hoping this changes drastically at 50.
Heh, I know that feeling. I wouldn't mind tanking now and then, or even healing on one of my capable characters. But I'll be damned if I'm going to spend the respec fee, which gets up there if you do it a lot.
Prior to dual specs coming in this will remain an issue as anyone who raids or wants to PvP and tank flashpoints will have another spec they play. Not many people will be keen to respec 5-10 times a week just to tank a flashpoint and raid as DPS.
I think a big problem is that half of the classes that can go tank have a tank as their first companion. This pushes people away from choosing the AC that can tank in favour of the other, and then it is imposible to go back. And levelling another of the same class just so you can have the other AC is kinda painful ubecause you see -exactly- the same quests +/- like 10 that work differently for light/dark.