FYI, it's been widely speculated that THQ is essentially going all in on Metro Last Light - evidently Metro 2033 was a bit of a critical success but never caught on because it had a number of bugs in the initial release that were subsequently patched - I have no firsthand experience, but this is the recent analyst talk. The idea is, if they can get 2033 out into enough hands now and enough people have positive experiences with it, then maybe enough customers will take a chance on Last Light to keep them financially afloat.
If not, well, speculation is Last Light may be their last major release before bankruptcy.