There appear to be two HDR camps... HDR10 and Dolby Vision. I would think that if the new TV supports both that would future proof "jumping the gun" wouldn't you?
You might not if you did a deeper dive into all the HDR schemes.
HDR is the TV buzzword for 2017—here's what you need to know
Samsung is promoting HDR10+ (with the help of Panasonic that doesn't offer TVs in the US) and there's HLG that is part of the ATSC 3.0 standard and is supposedly compatible with non-HDR TVs (think of a HDR sub-carrier much like stereo added to FM audio). There's also a scheme that I haven't seen much about called Technicolor HDR.
While Dolby Vision is probably the best of all, there doesn't appear to be a lot of content out there so you have to look for what format the content is available in.
If you're a DIRECTV subscriber, it appears that they've cast their lot on HLG. I'm not sure what other pay TV services are using.
Until the carriers "settle out" on a variable HDR scheme (everything
but HDR10), I'm not sure it is time to bite on HDR. Quite a while back I predicted that HDR would be the next VHS-vs-Betamax or HD-DVD-vs-Blu-ray format battle and it appears that the battle is only getting started and with a greater number of players.
Depending on how long you plan to keep your TV, there are other standards in play (such as surround sound and HDMI) that may also be important in the not-too-distant future.