In the anime, Yu's really a laid back, Nice Guy who enjoys sarcasm once in a while.The reason he seems so serious/dull all of the time is simple. His Expression is too low.
In a later episode of the anime, the Investigation Team will test the limits of Aiya's Deliver Anywhere policyNamely, by ordering from inside the TV World. And it will work.
Yu's reaction to Teddie's new look in the anime will be...Ces't Magnifigue.
In the anime, Yu is doing a New Game+.Specifically, Yu is on a quest to Set Right What Once Went Wrong because he reached the Bad Ending, letting Nanako die and the real killer go uncaught. His failure bothered him for some time, prompting Igor to do his Time Travel thing. Unfortunately, Yu does not have Ripple-Effect-Proof Memory, but he instead has instinct and deja vu on his side. This also explains how his Izanagi is so badass and how he has access to high-level Personas earlier; he still has access to his old Persona Compendium.
Chie will be the canon love interest in the anime.She's gotten way more romantic scenes then any of the other potential love interests. Although to be fair, Naoto did just get here.
Kanji and Naoto will get together in the animeJust a thought. Chie and Rise have had more attention as a potential love interest then Naoto so far, and focus is put onto Kanji's crush on her. The swimsuit contest really didn't help either. Perhaps the Christmas Eve scene, with Naoto putting on the female school uniform and all, will happen with Kanji instead of Narukami?
Aika will be the new female protagonist in The Golden.Her addition to the cast in the anime contributed literally nothing essential to the story, so why would the writers have gone so far out of their way to include her as much as they did? Most probably: they were using the anime to promote her because she is slated to have some sort of super secret special role in The Golden. What role, you ask? Why, acting as the all-new selectable sis-tagonist! Hamuko from Persona 3 Portable turned out to be incredibly popular, so why wouldn't they do the same thing here?
Yu has autism.He doesn't emote much (at least early on), tends to be blunt, can be described at times as eccentric, and has a fascination with folding paper cranes. Sounds like characteristic of autism to this troper (who, himself, has autism).