There's a separate app. for Pro subscribers?
I've used the regular service for one trip and it's good but it's better to print out the itinerary than to view the info. in the app. because if you're overseas, you won't have a data connection.
One thing I did was create an itinerary with pictures of maps (screen shots which I uploaded from my computer).
I noticed the iPhone App. doesn't display these pictures, especially zooming in, as well as just opening the itinerary on Safari at the TripIt site.
Of course Safari doesn't cache sites, tries to reload so again, you need a data connection.
For the printout of the itinerary, more print formatting options might be nice. On a color printer, the theme of the printouts is a drab yellow.