I played it by using a key from Fileplanet - $6 to try out a game that might well buy seemed fair enough to me.
I had the lag problem last weekend which made it unplayable - but I played on/off this weekend and made it to level 11 Chanter. Far enough along to get Wings and see the capital city (I think that thing must be the capital city).
Overall it's ok. It seems like a competent MMORPG but I didn't see what made it better than other games like WoW except that it's not WoW for everyone who is tired of WoW. It seemed well designed, and I liked the graphical style and the graphic details and effects. I didn't get to PvP - it's a shame they set the levels so high... I like the Warhammer "shove them into PvP at level 1" method and I wished that I'd tried PvP more before I passed my personal judgement on the game.
Based on comparable play time, at level 11 (or it's comparable level) I rank Aion:
1. Star Wars Galaxies - the original, way back when it came out, before Jedi (although I was on the server when the first guy got Jedi). SWG was my favorite - hard to decide where level 11 was in SWG tho.
2. World of Warcraft - by level 11, I thought this game was the greatest ever.
3. Warhammer - I liked this game a lot - particularly at the beginning.
4. Aion
5. Lord of the Rings Online - I could never get into LotRO
6. Age of Conan - Was not much impressed at all.
7. Vanguard - wish they'd had an pseudo-Open Beta like Aion so that I could have saved my money.
Never played anything else.
After I finished playing tonight I decided that I won't buy Aion. It was a close call. I really thought about it. I liked it, but not enough to buy it. Thought that a week's worth of play was worth $6 to Fileplanet though.