But it's sh*t
I don't use Facebook (often) or Live Search. However, I rekon that most people who visit Facebook will just whack in google.com in to a new window, tab, or whatever and be done with it.
Typing in google.com (Or .co.uk, whichever you prefer) isn't really all that tedious, and besides, Live search sucks. And don't most web-browsers have a search engine integrated in to the address bar anyway? Failing that most of them have a dedicated search box in the top-right anyway. Just type in what you want, Alt+Enter, and there you go, search results in a new tab.
I'm kind of drifting off the point that i'm making here, but basically Live Search sucks, and going to Google (Or whoever you prefer) isn't exactly a stressful task.