I agree the UI/polish needs a couple more iterations, but I used this to put together an itinerary for my upcoming short vacation. Really like the gannt chart style view as a planning tool and the ability to use the bookmarklet to save stuff for later. It kind of mimics how I plan a vacation now: decide where I'm going, find hotel and flights, then look for things to do.
And it's the looking for things to do part then saving them and creating an itinerary (now done poorly with bookmarks or evernote) that is a pain in the ass that this attempts to solve.
A few kinks to work out (would love to be able to zoom on the timeline or get a traditional day/week calendar view and also actively collaborate with my trip companion) but promising concept overall.