Games Similar To Fallout and Borderlands

You're thinking of id software's Rage

STALKER is the best free-roaming post-apocalyptic shooter series. Probably worth a look.

Oh, and there's also the recent Far Cry games.

Deus Ex Human Revolution comes to mind but it's on a much smaller scale. Can freely wander around the hubs, find side quests, choose how you want to solve them. You will gain experience, level up, find loot, choose how to handle conversations, trade etc. Good FPS/RPG.

If you would be interested in more traditional (turn based, isometric) RPGs then Wasteland 2 is a pretty good one. Post apocalyptic RPG of which the Fallout series is a spiritual successor to (Fallout and Wasteland 1 having been made by the same people). The Shadowrun games are pretty good too, especially Dragonfall and Hong Kong.

Came to say this as well.

I haven't played it but the Mad Max game looks fairly decent.

Try Rage, Mad Max, The Witcher is similar to Fallout. But honestly, RAGE was hella fun.