I play on JC and have heals, dos and tanks and only rarely have queue times longer than 20 minutes. During the week I play between 5:00 pm and 10:00 pm eastern, so pretty much primetime. My tank is normally instant queue, while the others are wait. I normally do dailies in ilum and BH while I wait. And the queue pops right when I'm finishing / turning in.
The issue is population imbalance which is something BW can't do a lot to address. They could offer incentives to roll tanks but then the other classes would whine. The solution is that more people need to roll tanks. As someone who has all three, tanking is really fun so roll one and try it out.