When I was playing WoW I read all quest text. When I was playing the SWTOR beta this past weekend I listened to all dialog, and this is a habit I'll continue into the official launch. The majority of the dialog didn't even seem to be that long, that could be because I'm so engrossed in what is being said and making my choices to the point where I'm just losing track of the time. For me the conversations in Bioware games are like a metagame, they're just as important as the combat to me.