scarbsf1 mentioned it first – retweeted someone who tweeted him about it, then seemed to confirm it a few hours later.
either way, looks like mclaren will announce a new staff member today. he first thought it was chris dyer (also leaving ferrari), but it doesn’t seem to be the case.
and i think costa to mercedes is a done deal – it’s just waiting to be confirmed.
as for what i think, sam needs mclaren more than mclaren need him, imo. i’m not sure what role he’d fill there, unless they need an additional man to help distribute the workload pat fry handled previously.