Tanabata is one of the summer festivals in Japan and it is celebrated on August 7th (depending on the region, sometimes on July 7th). Shibuya seems to hold the festival on August 7th and the town is preparing for it.
This is typical decoration.
Hachiko the Dog, the symbol of Shibuya Station was not in the tanabata style but he was encouraging people to vote on the election day which will be next Sunday.
One more photo from Shibuya is Disney store. Looks like you are in Disneyland.