I tried TripIt Pro for the trial period and wasn't really impressed. TripIt is a definite must-have and I use it all the time, but I didn't feel the annual Pro subscription was worth the asking price. I use a combination of "App in the Air" and "FlightView" to get gate, boarding and status notifications and found they work as well if not better than TripIt Pro when I tried it out.

My advice: definitely use TripIt but take full advantage of the Pro's trial period before committing for a year