I can't speak to the overall 'useful or not' question posed because I believe that's relative. As for it being a step to the future, I can say 'yes'. I think it's a "new-ish" technology that is quite complicated and has seen slower adoption compared to previous similar technologies. I think we're still in a transitional period that is seeing some acceleration by the release of Type-C/TB3 capable machines that's going on now. I do the possibilities that come with connecting directly to the PCI Express bus at 40Gb/sec, especially external graphics. The Razer Core to me is the epitome of the technology right now. I'll probably be getting one for use with the V.
I found a while ago that there are such things as cheap cables, and that quality /does/ matter. I've purchased around 100 USB cables of various types over the years, and found that the cheap ones; don't last, aren't easy to use, don't conform to spec, suffer from random other issues that I don't need to remember, or some combination of those.
More recently I've been into USB-C and Thunderbolt3 because of the V, but also because of my job. One thing I've found is that with USB-C and TB3, cable and charger quality matters more than ever. For striking evidence of this, check out the work done by Google Engineer and USB-C warrior Benson Leung and his counterpart Nathan K. https://plus.google.com/collection/s0Inv
What they find is .
In a nutshell, manufacturers are not paying attention to the USB Specifications when making their cables, more often than not they cut costs by using subpar materials, omitting necessary wires or programming the chips inside (Yes, the cables have electronics inside them that communicate with device AND charger!) to do the bare minimum operation. This causes devices and chargers to not perform the actions that the USB Spec allows for, and in some cases are downright DANGEROUS to the device (getting too much or different power and killing the board) the cable (too much power causes overheat and short) or you (charger catches fire).
Only a small percentage of cables and even fewer chargers meet the USB Spec and are considered (by him) good enough to use. I have been purchasing Apple chargers and cables because they've implemented their chargers and cables correctly and are widely available.
http://bensonapproved.com/ has others, but I didn't see any Apple stuff there. Can't tell if it's updated regularly.
For more information: USB Type C Explained https://plus.google.com/collection/0Vdov
Sorry for the novel