I am neither for or against it.
This is because I am single (single does not mean unhappy) and always have been so I do not feel like I am in a position to make a judgement on the most ultimate long term relationship when I have not been in any relationship at all.
I don't mind being alone for the rest of my life, but I am not going to run from a woman who loves me unconditionally because I am afraid of losing my freedom or independence, or the obligations marriage would bring. A woman who accepts me unconditonally like that may only come once and I would not throw it away for fear.
The one fear I think I would have trouble overcoming though is my ability to return that level of affection to my wife. I have befriended many girls who have poured out their hearts to their significant others and received nothing in return, and watched their spirits break because of it. I could not bear that burden, even if that lack of affection was unintentional and just part of who I am rather than malicious like it was for those women and is with many other men.
So yeah, I will cross that bridge and make that decision when I get to it. I'm pretty young, and I know I do not have forever, but I'm positive that this is something that should not be rushed into (including the decision to never marry).