I haven't been on steam for long before so this is entirely new to me, but darksiders II was 50 when I bought it (Wasn't on special) but is now $80. Same thing happened with Dark Souls, 40 Before release, 70 after release. IS this common for most steam games? Is it best to buy them before they are released?

From what I've read in other forums, publishers set those prices, and Australia always gets horrible prices.

So... why is it cheaper before it is released o.O

I have seen this comment a lot, I assume it has something to do with retailer agreements causing the price change once the game is on sale. They have to be at the same price as the boxed retailers selling the game.