NASCAR superstar Dale Earnhardt Jr. has called a press conference for tomorrow to make a long-anticipated announcement about which team he will drive for in 2008 and beyond.

Sirius willl air the Dale Earnhardt Jr. press conference live from the JR Motorsports shop in Mooresville, N.C. on Sirius NASCAR Radio (ch 128) at 11 am ET Wednesday.

XM will interrupt regularly scheduled programming on XM Sports Nation (ch 144) on Wednesday at 11am ET to bring live coverage of the news conference.

XM's sports anchor Claire B. Lang, who will report live from the press conference, is reporting that multiple sources have said they expect Dale Jr. to jump to Hendrick Motorsports (alongside Jeff Gordon and Jimmie Johnson).

ESPN is also reporting that Earnhardt will make the jump to Hendrick Motorsports Chevrolet in 2008. Rumors persist that NASCAR driver Kyle Busch will leave the Hendrick team.

Earnhardt is the host of the weekly XM show "Dale Jr. Unrestricted," which airs Thursdays at 7:30pm ET on XM Sports Nation.

Sirius is the exclusive satellite radio provider of NASCAR. Sirius broadcasts every NASCAR NEXTEL Cup Series, NASCAR Busch Series and NASCAR Craftsman Truck Series race, carrying the live feeds of MRN, PRN and the IMS Radio Network from Indianapolis Motor Speedway. Sirius also provides additional 24/7 coverage of NASCAR with exclusive programming.

Thanks Todd! 

(UPDATED to include Sirius content.)