Nicky Hilton talking on her cell in Midtown ... Rachel Bilson and Hayden Christensen watching the US Open ... Matthew Broderick walking on East 61st Street ... Taylor Swift posing for photographers outside her hotel ... Mickey Rourke walking his dog in SoHo ... Keri Russell going to Starbucks with a friend ... Ne-Yo walking outside his hotel ... Kate Gosselin getting out of a limo ... Gwen Stefani and Gavin Rossdale watching the US Open ... Bar Refaeli walking in the meatpacking district ... Mary-Kate Olsen leaving her townhouse with a friend ... Blake Lively walking in Midtown ... Cynthia Nixon walking on the Sex and the City set ... LaToya Jackson arriving at the Trump International Hotel ... Ed Westwick leaving his trailer on the Gossip Girl set, and going to dinner at Avenue with Jessica Szohr ... Courtney Love leaving the Mercer Hotel ... Oliver Stone standing on the set of Wall Street 2 on Park Avenue ... and Amber Rose shopping at Barneys on Madison Avenue.