Good timing. I'm visiting Tokyo in about three weeks. Unfortunately, most of the venues I'm seeing on Wanderant lack much information or context of why they're listed. Perhaps something more structured and editorial would help kickstart this before there are enough people contributing to the site.
Report
My take: people won't plan because there's just TOO much info. You need to propose a dynamic itinerary.
What you need is to make a proposed itinerary could based on 3-4 simple questions, eg:
"What kind of things do you like?" [Food, Art, Music, etc.]
Then you should auto-create specific things to do (card based)
"How fast do you travel?" [Pack it in <--> Leisurely pace]
"What's your budget?" [Only free stuff <--> Only the best of the best
"Do you like walking?" [Love It! If necessary! Motorized Transport Only]
Then it fills in your dates / times with things to do, allows you to book and refer to it as well. At the very least you can 'cycle' through options at a given time slot.
THEN people will use the explore function, but only after they've seen the result. Compare twitter usage when no one was following anyone. There was no content.
Riot
Product Hunt