Originally Posted by
CJKatl
The site
http://flightaware.com/ is often more reliable for gate information than the DL site. FlightAware has accurate information when the DL site isn't showing an arrival gate or hasn't been updated to show a gate change.
Flightaware is not free while in flight, though.
On the ground, I use a combination of the DL tools, flightaware.com, and flightstats.com for info on upcoming flights.