Day Four of Sundance is upon us! New arrivals include Sarah Jessica Parker, who visited Fred Segal at The Lift this afternoon below the MySpace cafe, Kirsten Dunst, Dave Matthews and Josh Hartnett.Also take a peek at weekend mainstays like Paris Hilton, who hosted a private dinner for Turning Leaf last night, then hit Motorola’s Late Night Lounge and private spot Butter with sister Nicky and her boyfriend David Katzenberg.Opening weekend fever will reach its peak tonight, rumors abound that Mischa Barton will slip quietly into town later for a spell of gifting at Boost Mobile’s suite and then, of course, a party or two. Movies shmovies! Check out all the Sundance celeb traffic.