Immediately:

* You can pack many more different colors into fiber optic communication lines. Every color carries a few tens of GHz in modulation, but the carrier light is in hundreds of THz; there's a ton of bandwidth not used between readily available colors.

* You can likely do interesting molecular chemistry by precisely adjusting laser light to the energy levels of particular bonds / electrons.

* Maybe you can precisely target particular wavelengths / absorption bands for more efficient laser cutting and welding, if these adjustable lasers can be made high-power.

Fiber has fairly narrow windows in which it is as transparent as it needs to be to go long distance. We're already pretty good at filling these windows with conventional semiconductor lasers.

What this is actually interesting for is being able to access arbitrary atomic transitions, many of which are outside the range of conventional semiconductors (too short, usually - there's a big hole between green and red for semiconductors). That's why they talk about quantum stuff.

* Concert lasers just got a lot cooler.