I would like to throw some more light on Orbitt's post. A few guild mates and I discovered this on launch.
Using this method you can go from 13-30 in one over night session. Going from 29-30 it only takes 30mins. I have 6 level 30's using this method in just a 2 days.
Method
-Get level 13.
Once you are 13, you automatically obtain access to the Alert Gorilla Island.
-Queue up for Gorilla Island Alert.If you can, get 3 other friends to queue with you and enter the instance together. If you can not, queue alone.
-Complete the instance completely. Kill every single mob.
-Do not leave. If alone, and with other random members, just go afk until they leave and you are alone.
-Go back to the beginning of the level. Where the Gorillas on the two upper walk ways were throwing barrels down on your head.
-Go up on to either walk way.
-Stand at the end of walk way on the far side from the beginning of the level.
Standing here, you can hit 2 barrels at the same time. Instead of just one.
-Use your ranged attack, right mouse button. Positions yourself just far enough so you do not get hit by the barrels explosion. Also, be sure to be far enough back, When you level, your player throws out a knock back aura that can move, but not kill the barrels. This will result in them not re-spawning and your character standing there shooting nothing but air. I use flight, and hover above in the air.
-Use your G15, N52te, autohot key, or w/e you use to automate a key press. Create a macro to use the right mouse button repeatedly.
-Activate macro and watch your character kill barrels, two at a time for 11 exp per barrel. This may not seem like a lot, but it is. Especially since the barrels re-spawn instantaneousnessly. You will have a constant stream of 11exp being added to your exp pool.
-Go afk/school, sleep w/e. It only takes about 5 hours or so to get from 13-30 providing your client does not crash, you dontt knock barrels away, or the servers don't get reset.
Please note. This is only for a fast way to get to 30. This will gimp your character as you will have zero rep, and no feats completed, this means you will not have very many skill points. You will still need to go back and complete all the quests. Although, it's much easier and faster banging out all the quest because you're 30 already