I base my opinion of a person off their "about me" and then their pictures (which, quite often, tell you even more about their tastes and values). If I see statements that are blatantly against things that I love, such as one day having a large family or the importance of humilty, then I move on. If I see statements that are blantantly against things that I care about, quite frankly, are not that serious (for example, someone who absolutely loves Maroon 5 or tomato soup) these things I do not identify with the essence of the person so I don't exclude them or pass them up because of this.
I made a checklist once...when I was 12. I haven't written one down since, for a friend or for a spouse simply because it is all in the will of God, not my own. I've met so many men and women who have impossible qualifications, and it saddens me because they are holding out for that perfect person whom they've devised in their heads when he/she does not and cannot exist in this world.