looking for map pinning plugin

Hi, I'm working on a pinterest-type site for travel - MyTripPost.com
One of the features of the site will be for visitors to be able to add a pin to a map saying they promise to visit someday.

I've seen plugins letting the wordpress admin add posts to a map, but I'd like to allow registered users add a pin (promise) to the map. The map would then display all pins from people on the site.

It should work like this
1. Map page would display all pins from other users
2. New user on the site would click on an area they want to visit.
3. Their pin would be added, saying "*username* promises to visit here"

Any suggestions are appreciated.

Thanks.