THQ's BIGGEST stuff has been Saints Row for money. But having that solitary bet of guaranteed income compared to the piles of drivel that they release or bet badly on is probably putting a dent in their bottom line.
Look at their STEAM catalogue. It's Saints Row, Relic (Warhammer/Company of Heroes) and a few of the niche war-sim games. Metro and Homefront are there, sure, but Metro was never expected to be big, and Homefront was a rather dedicated failure.
All in all, they develop either schlock (been digging through their various online databases... a LOT of movie tie ins), or rather niche games. The broadest appeal game has to be Saint's Row, and that's so over the top that you might no be able to get a parent to buy it in favor of GTA IV.
I can see them having to restructure, and maybe being bought out... but I'm not sure.