We kept our own last names. I had just changed my whole name, first middle and last, a year before we got married. I didn't want to change it again.
There was some idle talk over the years of my husband taking my last name, but it never happened. I currently lean toward eventually changing my middle name again and taking his last name for a change. No telling if I'll ever do it though, because changing your name as an established adult is a lot more annoying than doing it at 18 when you have no major accounts anywhere.
`Twas brillig, and the slithy toves did gyre and gimble in the wabe;
All mimsy were the borogoves, and the mome raths outgrabe.