Opinions needed

I was seeing this guy, and it was going well as far as I was aware. I knew a couple of months before he had split up from his girlfriend, but we never got into what happened, although I know he was fairly torn up about it.
Anyway another guy I dated briefly a year ago is friends with this guy and knew his girlfriend, got strangely jealous and basically went and convinced his ex to get back with him.
Anyway, he blew me off to try and make it work with his ex. This was about a month ago and they are still talking but they aren't back together.
My point is, I really like this guy and I am in regular contact with him and we get on. We always flirt like mad and I'm pretty sure he's still interested in me from the way he behaves, but he is still hung up on his ex.
Personally I feel like if someone else had to convince her to talk to him that it's unlikely to go very far, and with it being Christmas time coming up it may just be not wanting to be alone over the holiday. But I am bias.
Any thoughts?
M