The Demo for the game is available. I'm calling this a beta demo. The game still has some rough spots (optimization for one); so, I can't call it the official demo.
The demo allows you to explore Nerah's Landing (the starting area of the game), complete some quests including the beginning of the main quest. There are two dungeons I left open that are accessible from this zone: Temple of Solaris and the Abandoned Watchtower. Both are rather formidable for a low level party. However, I was able to get deep within the Temple with a certain group build before I was slaughtered by the boss. :)
All of the game mechanics are presented within the demo. I will say with the exception of using spell tomes to increase your mastery of a spell unless you are willing to grind mobs for a very long time.
If you grabbed the previous release of the file, grab the latest version. I updated it to include fixes for a couple of issues brought up by a tester. Also, I added a few mouse options in the configuration menu: inverse mouse, X and Y sensitivity. Something I overlooked and was brought to my attention by player.