I have not been to Five Guys, but being in the industry, I know that their hand cut fries are fried in Peanut Oil, which gives a unique flavor to the potatoes, but also makes the product richer and more filling.

The new "hip" burger place is called SmashBurger. I have not tried this place either, but from what I hear, they're running a good business and growing fast. They "smash" the meat right onto the grill, and then add the toppings you want. Milkshakes are made with Hägen Dazs Ice Cream. Also, their menu is a bit regional: Nor Calif: Brie Cheese, Appplewood Bacon, Balsamic Tomatoes, Grilled Onion, Spread, on a Sourdough Bun. Can't wait to try it, but not yet in Los Angeles.
http://www.smashburger.com/