Just my 2 cents anyway.
For more and more people, it's just a name, like "Fox" or "Warner Brothers". Most people don't even know about the original Justin.tv show, or who Justin is.
There's nothing wrong with having a brand name that doesn't explicitly say what the company does (reminds me of the Forest Gump quote "We invested in some apple company"). Their site get millions of visitors per month; they'd lose staggering amounts of brand equity at this point by changing names. Besides, I'm willing to bet that the vast majority of its users don't know the origins of Justin.tv.
Googling led to this for Windows: http://www.pcwinsoft.com/screencamera/landing.asp
