Lance Armstrong and Kate Hudson Hold Hands on NYC Date

They still won't admit they're dating, but Kate Hudson and Lance Armstrong have no problem showing a little PDA. (See other stars smooching here.) The two ' who spent Father's Day together with their kids and Hudson's ex Chris Robinson ' held hands during a dinner date at STK restaurant in NYC Tuesday. "They were celebrating the launch of LiveStrong.com, the web component of Lance's charity," a source tells Usmagazine.com. (Armstrong also appeared on the Late Show with David Letterman to discuss the site and his family. Watch the video above.) "They came in and left together," the onlooker adds. "They chatted with people all night" when they weren't snacking on hors d'oeuvres. Adds the witness: "They were very friendly to staff and signed autographs for guests who attended the party." Armstrong, 36, and Hudson, 29, first debuted as a couple last May at New York City hotspot Wildwood BBQ. Since then, they've been spotted together in the biker's hometown of Austin, Texas, and at the Cannes Film Festival in the south of France. See more pictures of Hudson and Armstrong's date here. Tell Us: Will Kate and Lance last?