Half-Life 3 to be an open world game like Skyrim?

Destructoid came across rumors that Valve's Half-Life 3 will take a break from the linear progress featured in the past Half-Life games and introduce an open world. The rumored launch date is "after 2013", and according to the source this open-world version is the third iteration of Half-Life 3. Development started as a more traditional shooter, before the game developer switched gears and started focusing on exploration and puzzles.

If the chatter is correct, Half-Life 3 will feature quest-giving NPCs to give Half-Life 3 a dramatically different feel. It seems very weird, given Valve's past content ... but weirder things have happened. In any case, it's something to think about, whether true or not.