Kim Kardashian and her mom, Kris, hit the boardwalk in Santa Monica yesterday to film a commercial for Skechers Shape-Up shoes. It's the latest product in Kim's endorsement empire, after she's touted items ranging from Campari liquor to Charmin toilet paper, QuickTrim diet pills, and even Carl's Jr. fast food. It wasn't all work and no play, as Kim tweeted a few kind words about being able to shoot with her mother. She wrote, "Couldn't have been a better day!" The posing jobs, in addition to her variety of E! shows like Kourtney & Kim Take New York, have Kim flying between the East and West Coasts regularly. She's in NYC today already and is evidently planning to plant some roots in the Big Apple for a while. Things between her and her New Jersey Nets player boyfriend, Kris Humphries, are so serious that Kim wants to move to New York to be nearer to him.