Well, so far I've enjoyed the PvE quite a lot. The "main" quest line is pretty well made with nice cinematic dialogues between your char and the quest important NPCs (I don't really dig the voice choices for females, but maybe they'll fix it up later). Also, the fact that majority of the dialogue is voiced and is presented as a cut scene makes it easier to follow the plot of the quest, instead of just clicking Next button a few times, because you're not feeling like reading all the text that comes before the quest objectives. Beyond that you can roam the land and help out in different areas as there's various conditional quests that pop up every several minutes (these quests make the leveling between the main story quests easier since you don't have to just go and grind mobs, instead you go do a local quest which involves killing something).
Another thing is that they are emphasizing the "I" and "my" as in player's story to the point of being cheesy and over-the-top. I do get that they want to make the story about your actions as a player, but your character pointing it out for your in dialogues and cutscenes is just too much.
What else, the graphics are really nice, maxed out on sub-1080p the game looks very nice, would even rival some of the single player games I'd say. The engine is a little funny though, as if you decrease the resolution you're playing at, for some reason it drops the texture resolutions too. At 1080p you get very nice textures. In-game you can enable FXAA, not sure about how well forcing AA through GPU works, didn't bother with trying. Another cool thing there was an option to enable stereoscopic rendering, but it didn't seem to do anything, unless I'm mistaken and that implies something else besides 3D-display mode. But if I'm not mistaken then they are planning to make the game playable in 3D mode, which is pretty neat.
In general I find the game quite enjoyable since there's a lot of things to do besides main questing. There's elaborate crafting system. There are bonuses you get for exploring the maps (mainly you get some exp for it but occasionally you stumble on some quest that gives nice rewards). There's also PvP and WvW, now for this beta you could tell it's still WIP, since NPCs were there, but had very little description to them. WvW is fun, I've tried it for a little bit, but then got tired of running around for 5 minutes before you get to any action and your ability to die to a simple pack of wolves. All in all I'd recommend that before you go into WvW at least to open up all the skills for the possible weapons that you will be using, because doing it inside WvW will take you forever. That said, I did see quite a number of people on the WvW map that I jumped to, so I'm guessing there's quite a fan base for that game mode. No comment on PvP as I didn't try it, the only neat thing about it is if you wish to see what a certain class would look like at level 80 with some skills, go into PvP training grounds, you'll be given all the skills and all the weapons so you'll be able to try all of them and see if you like the class or not.
Alright, that's all my impressions for now. I only got to play about 6-8 hrs total as most of it was in the evenings of the 3 days that the beta ran, while there were people claiming in chat that they've played for over 24 hrs straight...