[Berosus]

Yes, I have noticed the same trend since "Happy Days" dominated TV in the 1970s. Fashions, TV shows, etc. enjoy a comeback twenty years later, whether or not they were cool the first time around. In that sense, the only surprise is that these movies didn't appear a few years earlier. Maybe it's because we don't have a good name for this decade yet, and now it's more than halfway over.

[Ocracoke Island]

The 50s were retro in the 70s - you're right. I remember my sister dressing in 50s style clothes in high school, and my mom was happy to help her choose her clothes. I came of age in the 80s, and the 60s were definitely retro then. Of course, the 70s have been retro for some time now.

Where this gets really interesting - to me, anyway - is in the demographics of it all. The generation that came of age in the 80s is smaller in number and therefore less dominant in general cultural trends than either the 70s generation or the 90s generation. So, 80s retro will be both less prominent and shorter than either 70s retro or 90s retro.