I'm honestly not sure where to start, graphically it seemed beyond what I would expect for a F2P title. Performance, playability, and engagement (in an early alpha build) was rock solid. I went back today and played for another 30 minutes. SoE dedicated a very large amount of their booth to the title and I spoke with quite a few people who had played the original Planetside.

Personally I felt like it had the addictive nature and ease of gameplay that Battlefield 3 has, with the visual style that Planetside shared with Tribes.
I also felt like I had a better understanding of the battlefield situation from Planetside 2 then I have playing BF3. At any given time I could ascertain what my team, and my enemies were doing without pulling my attention away from the actual combat.

I can write up some more impressions about it later, Im going to get sleep.