From ESPN;

#9-Kasey Kahne, the hottest potential free agent in NASCAR entering the season, has signed a multiyear agreement to join Hendrick Motorsports in 2011, multiple sources close to negotiations confirmed to ESPN.com Tuesday. The details of the deal, such as which car Kahne will drive, are still being finalized, sources said. The prevailing thought is Kahne will occupy the #5 car currently driven by Mark Martin, sources said. Martin signed a contract extension last year through the 2011 season. There is room for Martin and Kahne in the Hendrick family. Stewart Haas Racing receives chassis, engines and technical support from HMS. So Kahne could be housed there until Martin's contract was up, if necessary. In 2008 Dale Earnhardt Jr. signed a five-year deal with Hendrick. Jimmie Johnson last year signed an extension through 2015, and Jeff Gordon has a lifetime contract. Kahne is in the final year of his contract with Richard Petty Motorsports, and plans to finish the season in the #9 Ford, sources said. It is unknown whether Kahne's sponsor, Budweiser, will accompany him to HMS [which sponsored Hendrick's #25 Chevy for years]. Hendrick Motorsports officials had no comment. Calls placed to Kahne, who turned 30 last weekend, and to his agent were not returned.(ESPN)(4-13-2010