Heavily dependent on the circumstances. If there is no right turn lane and just a bike lane or shoulder I'll filter up to the front. If there is a right turn lane then I don't want to pull out into potential traffic just to cut back into the straight lane. If the road is a high-speed road and the cars will pass me immediately then I'll wait in line. If it's a dense urban intersection then I'll pull to the front since car/bike speed is not too different in my city. If the cars decided to pass me right before the light then I'll pass them since I want to mess with them. There are infinite scenarios, but it's interesting to hear how others do this. Good question.