When to go to new world??

This may seem like a trivial question, but I wanted to know the reasons for either

1: Staying in the begining world, before the fall etc, or

2: Going to the second age, where you cant turn back..

There seem to be a fair amount of quests in teh first age, and I'm trying to find a reason to either skip all the quests and exploration available there, and dive ahead into the second age..

seems like an aweful lot of nice quests, models and scenery that I wont see unless i explore a bit..

Your thoughts?

My suggestion is play the game.
Do the quests that are relevant to your class combination.
Upgrade your equipment, have some fun.

You may be experiencing new content that wasn't available during the beta events. Why rush to get to Lvl 20 when the game is so rich in things to do?

Stop and smell the roses my friend.

Mind

I would suggest staying in pre-searing until at least level 6. Get all the skills you can for your primary and secondary professions. If you've had enough of the pretty scenery by then then go ahead and enter the academy, otherwise stay and sightsee a bit more.
The good thing about post-searing is that there are better items available, better armour, etc, you can have larger groups and you can have henchmen.