In addition to iPass working consistently on DL domestic and especially international of late, I was able to get full GoGo access this week when flying GOL GIG-VIX-GIG.
BTW, even though this is a short flight (GIG-VIX) any user can access Gogo for entertainment during the flight and one 737-800 I flew also had a little tray on the back to the seat to rest your smartphone.