well, if I was playing tonight I would get to level 24 (30-45 mins play time) and then come help out. But my friend who egged me on to (obtain) some movies last night, wanted me to catch up with him. So will be doing that instead.
Word of advice, if you can complete quests (easy ones, green/yellow) by yourself and do like 2 or 3 at a time (within 1 hour) then you will level very quickly. When questing with others, the quests become very easy, try and double the number of quests completed within 1 hour (6+) and you will level at the same speed. Because the XP gained from killing mobs is divided between the players.