ESPN International has bought three international web properties this year - a rugby site, a cricket site and now the Racing Live sites. Going NASCAR with RL would be like making the rugby site a football site. ESPN is very smart re online so not something they would do.

Re pay models (my day job is analysis of digital entertainment business models)...

... I would be surprised if they change the current RL model much. RL already has both free ad supported and a pay "premium" service with added services, similar to what you see at NASCAR.com (run for NASCAR by Turner).

Pay models overall are in decline online in favor of ad supported. All the US ESPN online properties I can think of are mainly free ad supported, with fantasy sports being an added pay service. ESPN360.com is a special case, you don't have to pay for it, but your ISP does.

Even Autosport.com backed away from pay, mainly. There's still some extras you have to pay for, but most of the content went back to free.