As for must go.....
2014 is disneyland's 30th anniversary
Bullet train (shinkansen) 50yrs
Tokyo station 100yrs
Def a good time for japan.
Sensoji at asakusa is the typical tourist spot but worth a visit.
Tokyo skytree is new so might as well.
Akihabara is a must go for electronics, anime, manga, AKB48
Tsukiji for the fish market
Shibuya to see the multi road scramble walk
Harajuku for takeshita dori, meiji shrine, omotesando
Shinjuku just plenty of shopping I feel
Ueno has this "street market" called ameyokocho
These are the few places i never get sick of. Just keep going back again and again.