It seems both sides of the aisle are well represented in this thread. Since i got engaged last August I'll throw in my opinions.
A lot goes into the decision to get married. I would say that the biggest thing is where you feel you are in life, and your own personal values.
I saw several of the naysayers post that 25 is too young to be even thinking of marriage, since you can still be going out and meeting new girls. That is a fine opinion, and to some people that is the right path for them. The "proper" age can often be determined by where you live. People from larger cities tend to wait longer. The thing is though that it is you who makes the decision, so you shouldnt be basing it on what others say. Making the commitment to marriage requires the ultimate in getting to know yourself and what you want in life.
The naysayers may have a fit to know that i am 22 and will be 23 when i get married. I am ready to move on though into that stage of my life though. To be honest my personality is an introverted personality. My whole life i have never had a huge group of friends that i am only sporatically in contact with, but a very close core group. I went through my period when i was younger and trying to figure out who i was, and tryed to be someone I'm not. I realized though that i wasnt happy while trying to do that. I went out to bars and clubs with my friends, just to do what was "cool", when i dont drink, i dont smoke, am quite religious, i don't like loud music, and i don't really enjoy dancing. Parting of growing in confidence is growing happy with who you are.
Well by getting married at this age, when I feel ready, isnt a problem. I haven't had to "give up" anything. I still have all my friends, i still do my hobbies, i have not changed my political views or religious ideas. I still have my own character and identity. Maybe i am committing a cardinal sin of this board, but I feel ready to move past the stage of random girls and hookups. My goal was a long term relationship, and i have improved myself from a self-defeating AFC when i came here and acheived my goal. The amazing thing was that i came here hoping to find a quick "whats the secret line i have to use?" and left with a complete new self image, confident in my decisions, which turned out to be the real path to success. I'm not in a rush to move my life on in the relationship arena out of college while reataining the college lifestyle. I have one semester left and to be honest I'm ready to begin my career. So my relationship with my fiancee has progressed at the same rate as my life and I feel I am ready, rather than an arbitrary number that says "27 is the proper age."
I am amazingly similair to my fiancee in many ways, which i think has contributed to our successful relationship. In the ways that are most important for long term stability. Both of us liking soccer would be great for a first few dates, but I am very conservative politically and morally, and if she intended on raising our children that abortion is wonderful, the word God should never be uttered in a school, and hated Rush Limbaugh, Sean Hannity and Michael Savage, there is no way she would be right for me. Well we do both agree on these issues such as how we will raise our children, on how we see the role of God in our lives, how many children we want, career goals, and other items that are very important in the future. We both come from similiar backgrounds, share a similiar view on the value of money (she is not a wild spender and neither am I). We are both attracted to each other sexually. Looks get you the interview, but if you are not compatible in the above areas it won't work out. I've turned down girls i felt were too liberal even though they were hot because that would have been a conflict waiting to happen the second i made a passioned comment while watching the news. It may sound silly to say, but i honestly believe God intended her for me.
The long and short of it is, I'm ready for the commitment of marriage, I am positive i have found the right girl for me and she fits every prereq i had, and I'm excited about the prospect of rasing a family with her. We put our trust in Jesus to take care of our relationship and give us strength in the rough times. That's what i want in life right now. And if that is what you want in life, and you have the right partner for it, then you will not be losing anything and i wish you the best.