Yeah.. what PEN said.. Why would Aion need to release a trial? You do realise it had 400k prepurchasers, has stayed in the top 4 on xfire every day since it's been out, and actually had troubles at launch because TOO MANY people were playing. There is no chance in hell there will be a trial for a while, and I don't see anything wrong with that. Maybe if somehow they lose 90% of their subscribers in the first 2 months they'll realise something is up, but right now it's been the most successful launch since WoW.
Calm down first month of launch means nothing. Now after a couple months theres the data you need to analyze. Because those people are the real players.
I would assume they'll be releasing a trial within a few months, because I think a lot of their other games have trials. Although I believe the beta was free, that's about as close to a trial you'll ever get to a brand new mmo.
