I like how you use white space to imply depth.
#82 is very cool, just a bit too skinny and fragile for my taste... I also don't get why there's a box around the "HOT" in "photo"
#78 and #79 have depth, but they feel like elements floating in space instead of a solid icon shape.
#77, #76, and #75 all look like they say "OP", "UP" or "P" to me.