as far as i know GM announced the car back in august last year (they were forced to announce due to a leak) and has had it featured on the cadillac website under 'future vehicles' along with the ATS and the XTS (which will soon be moving out of that future vehicles section)
not sure what other kind of confirmation you need
also, this is two week old news ... and an article about a speculative post by GMInsideNews ... there's info leaked from onstar about the 2014 vehicle lineup and the ELR was on there
... so the only real news here is that the ELR will be a 2014 vehicle ... but we kind of already knew that ...
keep your eyes posted to this ELR sub-forum for news though ... if it's ELR it will be here