I wouldn't mind a cultural section. Like tips about customs in a place, so we as travellers can be respectful of the cultures we are visiting.

Purpose of my trip is to visit family and old home. Allowing for non-web activities, especially in itinerary would help.

A pay pal account and page for the host to have access to, where participants of the trip can periodically contribute their portion of the money for the trip. It would be nice to keep track of who has paid and how much people have left to pay. It would also guarantee that the money is available for the trip. The contributors can't touch it until the trip starts. It protects your trip from misbudgeting!!

integrate suggestions how to come from one point to the next

I want to send this itinerary to my family without them having to log in (being invited by me) but a print out just does not work in this case. So a download or save as pdf would be fabulous!

Possibility to have Items "fuzzy"-scheduled, e.g. floating inside a week, but still in the Itinerary.
Use case: Collecting lots of ideas and then deciding which to actually do by moving some into the Itinerary, but not knowing (yet) what exact days (depending on weather, mood, etc.)

How would one put the start city as the end city also. Errors in duplicate entry, when I tried entering location in this order:

1. Tokyo 2 nights
2. Kyoto 3 nights
3. Osaka 2 nights
4. Tokyo 3 nights

It would be great to be able to see the itinerary in a calendar view.

How about a little better job on the graphics. The current ones are a little cheesy.

Putting gps coordinates in the address field seams to find a place close to the coordinates, but not at them. Would be handy to be able to recognice coordinates in the address field. For example the trailhead of a hike might get stored that way.

Safari support

Takes two clicks to save a 'note'. A few times when I first (thought) I'd saved it, I hadn't. Easy to adjust once I knew, just a suggestion.
Have only just started with Planapple so no doubt tech genius Bro will come up with more.

An additional feature to the Itinerary that allows you to detail how you will get from one location to the next. (eg: travel time or travel method - bus, train, car, taxi, foot, etc and maybe even travel cost)

iPhone App

The facility to insert an attachment, like image, pdf, etc.

Allow more than 10 tripmate invites at a time

Amazon app, please

Ability to import PDFs

I can't use your site because we like to take road trips and camp but your "Stay" feature doesn't offer the ability to search for cabins or campgrounds.

add transportation search (google maps based) and calculate times.