I don't know that "theme" is really the right term, but it's what we're using.
Last year's was blatantly 90s 80s stuff.
This year there are park icons in ALL of the shirts.
There's some initial speculation that maybe the icons for each race are going to be indicative of the course. For example:
- the 5k only has epcot,
-the full/goofy/dopey have all 4 icons
but where this theory gets iffy is:
-the HALF has epcot, mk, and a dinosuar on it? Does that mean AK, or the dino in the pond in HS? OK so I looked and it's clearly Gertie from HS. And what's the deal with the boat? (Or is my memory really bad and that boat is also in HS?)
-the 10k has MK and Epcot. Does that indicate going back to the older W&D 10k course that started in MK?
And last year the 10k had all of the park icons.
It's nice that it's a cohesive set, and that touches in all of the pics have consistent parts (fireworks, the lines with the white dots, etc)