For questions like these, it always depends on other things.
I agree with itrick. There are many things that go into a relationship. And depending on both partners' histories, circumstances, and needs, age may or may not matter. To say resolutely that age gaps are good or bad is to ignore those details.
When I was 19, I dated someone who was 38. It was easy for us to talk because we were interested in a lot of the same things. Aside from my maturity, it helped that there were several things that made him seem a lot younger (but not necessarily less mature) than other men his own age. He spent about 12 years training as a professional olympic athlete and was very fit. Then he decided to go to grad school, which was in a field that generally takes students more than 6 years to finish. He was never married and had no children. So by the time I met him, he never had a "real" or "traditional" job, he looked very young, and he didn't act like a pessimistic single dad. He was like any other mid-20s grad student, except more well-mannered than anyone I had ever met. It didn't work out, but I still consider this relationship/friendship one of the best I ever had.
And when I was 17, I dated someone who was 23. I was more mature than he was, and it was fun. But he was more serious about it than I was.
I recently read a few articles that claimed men benefited in terms of how long they lived from marrying younger women. The younger the women, the longer the life-span for men. For women, it's totally different. Women had shorter life-spans with any age differences in BOTH directions. So women didn't get any longevity benefits from marriage, period. The only way to avoid a decrease in life-span was for women to marry someone exactly their age. And keep in mind, even in marrying someone the same age as her, there was no added benefit, only the avoidance of a "penalty". And in any case, all of this research I've mentioned might not matter in the face of love. It only matters if you believe in probabilities/statistics/extending your life, or whatever. :tongue:
If age gaps matters to you, then you'll probably never find yourself dating someone much older or younger than you. And you'll have that opinion for other people.
If age gaps don't matter to you, then you probably have dated/married (or knew a successful age-gap relationship/marriage) much older or younger, and it worked out well for you. And you'll have that opinion for other people.
I've dated many guys my own age, and for the most part, didn't like the experience very much. With that said, now I'm dating someone a year younger than me, and I'm enjoying it a lot.
Let us be not so quick to judge, so that we may evaluate situations for what they are rather than what we want them to be.