Depends what is meant by "marriage".
On the one hand there is the formal recognition "allowing" you to be married. IMO that is (rightly) dead, with the exception of the need for any tax breaks etc. The idea that government should give tax breaks to influence such an aspect of how people live their lives is pretty unsavory IMO, but that's another subject...! If you want to be with someone I don't see that it needs any outside "permission", be it state, church or whatever.
On the other hand is the aspect of celebrating what you feel about someone else, and doing so in front of those you care about. To me that is very much alive, but I don't see that it needs to be called marriage. It also certainly needn't be "THE WEDDING" which we are all brain-washed to have at ridiculous expense - that totally misses the point for me. My wife and I had a perfect day, away with close family at a place we loved and just spending time with everyone. Give me a million pounds and I doubt I could have made it better.
I knew a minister, sadly now passed on, who used to say that he felt society had things the wrong way around - it should be harder to get married, and easier to get divorced. Intent being to ensure people know what they want, know what they're committing to, but having done so should not be forced to live with a mistake. I'd tend to agree.
What are others' thoughts and opinions?