Interesting. However, the article overstated the potential range of the system. While a system like this would easily be valid within and nearby the solar system, it certainly wouldn't work at an arbitrary point in the galaxy. The beam of a pulsar is relatively narrow, so as soon as you move out of the region of space swept out by the beam the system would break down. (Of course, this could be trivially be worked around by incorporating more pulsars, but that goes beyond the scope of the original article.)
Agreed, the article is discussing interplanetary navigation, but the title is hyping it as interstellar. Whilst pulsars might have the reach to cover the local bubble, I would hardly call it interstellar. If your travel between planets only includes a handful of stars it would be far easier to track them than use this system.
Probably the best way to navigate on a galactic setting is to use the galactic core as a type of sundial. There's very little point of navigating off the galactic point, unless you'd prefer to die in very empty vacuum instead of merely empty vacuum. So all you need to do is select a set of galaxies aligned with the plane that are bright enough to track from anywhere in the galaxy. The core obstructing one of these galaxies would put you in a (relatively) very narrow band of space and the obstruction of two would define your position even more. The pinpoint accuracy can then be computed over time by triangulating between the remaining visible galaxies.
To be honest, it's not like you're going to need instant information updates in interstellar space. To even use a visual measuring system you have to be travelling at non-relative speeds, which then means you don't have to worry about hitting that star in front of you for at least 5-10 years. I'm sure a pocket calculator could compute the angles to find your position in that amount of time.
Navigation at relativistic speeds should be quite doable with a simple transform in your visualization system.
This navigation system can be used around multiple stars, hence it's technically interstellar, like a local hick-town airport that gets one commuter flight from Canada is technically international.
