While back couldn't send messages from my yahoo.co.uk address to hotmail adresses. Could reach all other addresses, plus I could reach the hotmail address from my yahoo.com address. I told yahoo about this problem; they told me there was a problem with my service provider. Which I doubt, unless my provider hates both yahoo.co.uk and hotmail but not yahoo.com

Haven't tried sending anything to a hotmail address in a while, but I guess a yes to your question would be in order.