He will decide late, or is probably not running. He is happy where he is.
In his new book, there's a chapter where he imagines how his obituary will read (in the context of how any time the media reports on him they start out with "No Joke," bashing you over the head with "oh yeah, this guy used to be on SNL") and he lists himself as a former three-term Senator. Taken at face value, that suggests he runs for re-election in 2020 and then retires in 2026.
Also, if Klobuchar vacates her seat and a Democratic governor gets elected next year, they could put Keith Ellison in her seat. Senators Franken and Ellison. I just jizzed a little.
I think the skinny repeal would have passed if the process started in committees, but here we are. Too late to start over.
In terms of future tries...midterm season ensures next to nothing will get done next year. This was their chance to do it, and they fucked it up. Then there's the issue of Trump's eroding popularity, even with his base. How popular will he be in January or Feb 2018? The party is already distancing itself a bit, they could be in full retreat mode by then.
That's the best part about how this went down IMO. If McConnell had played this fair and square, he probably would have gotten a bill passed. But no, he wanted to get out in front of any negative coverage by rushing it through as quickly as possible without anyone seeing it, to the point of flying a dying man out from Arizona to deliver the decisive vote.
There's probably been bigger but I can't think of a worse self-owning than what McConnell did to himself.