Just finished Borderlands 2. I will admit the ending was really good and the fight to get there was quite the challenge. According to Steam I have 75 hours in which included lots of wandering around, some online play and the side missions.
The nice thing about finishing the main story line is that you can continue to play and choose to start over in true Vault Hunter mode. I may continue to play a little here and there so we'll see if I can reach the magical level 50.