Facebook is one of my procrastination tools of choice (Friend me!). I wouldn't say I'm addicted; I know people who spend a lot more time on it than I do. But I've been known to spend my time reading random status updates, and joining groups like Petition to make it law that bendy buses make accordian noises when they go round corners (Well they should!) when I need a break from work. And being a big science geek, I join all of the pro-science groups, including pro-evolution groups.
However, there is a meme that's been propagated throughout a lot of these groups, which has culminated in the group: Evolution is not a belief, it is something you accept. This is obviously a reaction to religious anti-evolutionists equating evolution and creationism by suggesting that they are both "just beliefs." Of course this is nonsense. Evolution is based on observable evidence, and has changed over time as new evidence is encountered, just like any good scientific theory. Creationism is wishful thinking; believing the Bible is true, without question because otherwise, you might have to question other things written in the Bible as well.
That said, I haven't joined the group, because the title itself is completely false. I hold a belief that evolution is true; that's what it means to accept evolution. We should not allow the religious to co-opt the word "belief." It has several meanings, one of which is incredibly important for epistemology (theory of knowledge): the psychological state in which an individual holds a proposition to be true.
Most theories of knowledge require that someone belief a proposition (let's call it P) to know that P is true. The standard view defines knowledge as justified true belief (and some way to deal with Gettier cases, which I'm not going to go into here). So for anyone to know that evolution is a correct theory, it is necessary for one to first believe that evolution is correct. Without belief, it is very difficult to argue that one can know evolution is true.*
As the great prophet Carlin (pbuh) once said: "Let's try to pay attention to the language that we all agreed upon." The fact that one can believe in evolution doesn't put it on the same plane as creationism. I don't disagree with creationists when they say that evolution and creationism are both beliefs. I disagree with they say that they are both just beliefs. Evolution is not just a belief, to me and those who have taken the time to learn about it, it is a justified true belief.
* Even if we accept that evolution is a belief, it can still be refuted that we know evolution is true, based on our justification. While I believe that we have an enormous amount of evidence supporting the theory, a skeptical** view of knowledge can assert that it is impossible to know anything using induction (see Hume's argument).
** The skeptical view should not be confused with the normal meaning of "skeptical" or "skepticism." Epistemological skepticism a theory of knowledge that we do not, or cannot, have knowledge. Although general skepticism isn't very popular, arguments for limited skepticism: the idea we cannot have certain types of knowledge that the standard view claims that we do have, are strong arguments.***
*** I highly recommend Epistemology by Richard Feldman, for anyone interested in a good introduction to epistemology. It contains a good description of both the Standard and Skeptical Views, as well as a variety of theories about justification. It's also very accessible and relatively easy to read, even for those who aren't well versed in philosophy.