That's more than the blinding laser indeed. That one is fired from the surface of the planet. You can hide it under a big styrofoam rock or whatever. So it's a real advantage that can only be possibly countered if its location is discovered/known and prone to attack.
Relying solely on the information from these two links, I understand this thing as a "single-use" rocket-delivered mini-anti-satellite satellite. So if you can take the rocket down before it reaches orbit, say, with a laser-equipped 747, the thing won't be able to deploy and hit any satellite at all.
So you can certainly blind a satellite easily and for as long as you keep the emitting LASER source safe from aggression. But since this thing is launched by a rocket, there is a possibility of shooting it down. As far as I can tell from the two links it can only be used once, to kill a second satellite you have to launch another rocket, unless you can fit more than one unit in the same rocket or create a different model capable of hitting more than one satellite. Either way, this one kill per satellite means all you have to do is launch another observation satellite. You may loose one but that's no problem if you have a spare one. How much do these spy satellites cost anyway? Better leave this question unanswered. :rotfl:
I don't know how easy it would be to intercept a rocket before it can reach spy-satellite orbit, that's for the strategists to figure out. How well-protected the launching platform is, how close you'd need to get that 747 to be able to destroy a big rocket (or just melt the cargo if that kind of targetting is possible), for how long you can keep firing and shooting them down, etc.
Granted, if we're talking about war you might aswell keep Alert 5 on the launching pads and keep stuff ready to destroy them at the first sign of trouble. I guess the point would be to have a satellite destroyer up there already before any war starts, launched during times of peace, like this test. Then it's already too late and it would require a conventional rocket attack or another satellite destroyer to take it down, the anti-mini-anti-satellite satellite, which would probably arrive too late anyway, after the first satellite had already done its job. This seems by far the best option. Especially if you could disguise it as a fully-functional Weather satellite.