Sirius and XM Radio to merge? Shares of satellite radio operators XM Satellite Radio Holdings Inc. and Sirius Satellite Radio Inc. rose Friday, on speculation that the companies might merge or combine in another way. "We believe a 50/50 enterprise value split or perhaps a slight premium to XM shareholders may be warranted in a merger scenario," Stifel Nicolaus analyst Kit Spring said in a Thursday client note, keeping a "Buy" rating on XM shares. RBC Capital Markets analyst Ryan Vineyard in a Friday note to investors said a combination would generate long-term value for shareholders, given slow retail channel growth. Advertising, office, retail incentives and other synergies total between $5 billion to $6 billion, he wrote. Vineyard believes XM would need to be the acquirer, since it has 7.6 million subscribers to Sirius's 6 million.(Business Week), so..what does this mean for NASCAR Radio, which is now on Sirius? no idea, but looks like total speculation at this point.