Of course, there are some practical limitations to invisibility. They discuss some of them in that article. Because all you're doing is bending light around an object, the "cloak" has to be specifically tailored to the situation. That means if you leave the same plane as the object, or the object (say, you) moves, it becomes visible. Perhaps the most inconvenient aspect of this technology, is that bending light around an object means that light doesn't reach that object. So if you cloak yourself, or, as they suggest in the article, cloak a tank, no one will be able to see you. Unfortunately, you won't be able to see anything whatsoever - it will be completely black.
So, what's the application to architecture? Don't worry, although I do just like talking about invisibility, there actually is one! Scientists have theorized that the same sort of ideas could be applied to buildings to make them "invisible" to earthquakes! By creating large, concentric, plastic rings around a building, you could potentially bend destructive surface waves around a building, leaving it virtually untouched while everything around it crumbles. You can check out the full article on New Scientist.