That is how small galaxies become bigger, by feeding on smaller galaxies. But the thing with the Milky Way and Andromeda, the Milky Way may be bigger than Andromeda, but Andromeda is nearly 3 times more massive, so when that would happen, I'll bet that Andromeda would feed on the Milky Way, and not the Milky Way feeding on Andromeda.
While they may be accurate, what could stop them at 2012 simply because they made some story up about 2012 being the end so they dont have to do anymore calendars. Which is why I'm betting all my friends 20 bucks that the end of the world isn't coming in 2012, which I'll win either way because if it does end, I'll be dead so I wont have to pay it if I lose MWAHAHAHA!
Yes, but some scientists and astronomers think that we could have better tech to prevent that from happening if we're still around