How can it be, a user wears a different outfit on the forum than on the dance invite? I know, first thought: they just switched in wardrobe and it's a caching issue. But it happened again with the very same user after quite some time.
I'm not sure if it's the same user you danced with, but I know at least one person does this by layering foreground/background items in front of their HA so it appears one way on the forums, because those types of items don't appear on the dance floor (like it automatically removes the background items when you dance), so they have their HA base with a different outfit on under that and it appears different but really they're just wearing everything together and using the feature of the automatic removal on the dance floor to make it seem like they have two different outfits.
ohhh... thanks for the explanation! I didn't know, not just fore-& backgrounsds get removed but also layered clothes. Interesting.
I think it might be major caching issues. I'm wearing different outfits on the forums and on the dancefloor at the moment and it's been over 24 hours since I was last officially wearing the dancefloor outfit.
Edit: Fixed it on my end with a hard refresh.
I cannot get my outfit to update on the dance floor. It just stays an older outfit.

...removing background items on the dancefloor doesn't work this year, though. They finally got the people to appear instead of place holders. But the ballroom looks gross with all the rectangles obscuring the other guests :-(