Saw this today on my Facebook profile. Facebook are clearly trying to use their new found might to encroach on the hallowed turf of the browser home page. The home page has been the prize of Google for many years, and it's quite novel to see another business vying for this position.
Facebook are probably the only organisation in the world that could potentially make a dent in Google, and it looks like this is exactly what they intend to do. The next year is going to very interesting.
What is also interesting is that I haven't seen a 'set as my home page' button for about 8 years! It's actually kind of retro (in the Internet world anyway). Love it!