https://www.youtube.com/watch?v=f3BNJuTO7KkValve put out a RED and BLU vinyl record with Team Fortress 2's soundtrack on 'em, it comes with a code for a special in-game hat that is a record player placed atop the character's head called 'Audio File'
There's a case that has the records in a paper sleeve and the case itself has various head shots of the characters on it plus injured versions on the other side, then the inside of the case has various photos from Expiration Date, Meet the Demoman, Meet the Heavy, and various never before seen shots of the group, characters off on their own, etc
https://www.dropbox.com/s/j5l2turqe2pavxa/PhotoScan.jpg?dl=0This is a high-res scan of that entire photo compilation by a user named 'Political Gamer' on Facepunch
https://www.youtube.com/watch?v=v-v7kctwoecAnd on the vinyls are secret/hidden ambient tracks, some of them are from maps in game, like birds sounds, rain, but then there is one track that stands out as it sounds more like a jungle, which is an upcoming themed update, so it's possible that this is an actual hint toward that update coming sooner rather than later
I love how clever Valve gets with their hints and easter egg hunts