This is it. No waffling, no sidestepping, no lawyerly weasel words. The Equal Protection and Due Process Clauses of the 14th Amendment apply, and marriage equality is the law of the land.
The final paragraph of Justice Anthony Kennedy's opinion is a thing of beauty.
I also found this quote from Thomas Jefferson to be very interesting.
This parallels what Anthony Kennedy pointed out in his opinion (and I can hear the echo of the Notorious RBG's tart rejoinder during oral arguments, when she said, "There was a change in the institution of marriage to make it egalitarian when it wasn’t egalitarian. And same-sex unions wouldn’t — wouldn’t fit into what marriage was once."). The entire opinion is here; in particular, read pp. 6-7 and 20-21 (and then the whole thing, as it's quite good). The institution of marriage has changed over the years, as our entire society has changed; indeed, no nation can remain the same for two hundred years and survive. The beauty of our Constitution--and in particular, the 14th and 19th Amendments--is that it not only allows for such changes, it demands them.
This is the right opinion, written by the right judge at the right time.
"Oh what a lovely day," indeed.