So far, I'm liking what I've had time to do.
I have been doing the Tixx dungeon stuff. Made it to both the Grove and Divinity's on both my accounts. Very easy to group up with people and the dungeon is pretty forgiving and fast (15-20min easy).
I didn't realize this until I was looking up a possible bug in the Smash the Town achievement, but I think the little miniatures on the ground are actually a representation of Tyria, with each major city represented. That was cool.
The Tixx stuff itself is pretty easy without much fighting necessary. You really only have to defend a point for a few minutes and take down Toxx. The Grove version started with killing Tar Elementals, Divinity with present collection. You do have to take out turrents at one point too.
Don't forget the chest in the middle when you're done. And it offers you webs or glue (you will need both to make a mini) and other stuff you'll need to make up to two minis (if you do all 5 days). Not sure what will happen once it gets to LA. Repeating will only get you gifts and the chest. Some decent exp too (only on first run) if you want it (got my mesmer from 70 to 72 doing the first two events.)
It counts for your account, fyi.
The Bells: If you've played and enjoyed Rock Band or Guitar Hero, you might like this. You pick an area, then which of 3 parts of a circle you want to do. I've heard that certain areas are easier than others. There will be 8 colored wedges leading down to the blue circle with a white border you are standing in. Once they pass the white line, you use the appropriate skill key (1-4, 6-9). Counts for two titles and sounds very pretty. Kind of peaceful. Sadly, the songs are just from the in game music. A few more recognizable Christmas songs would have been nice. There's a free play chance for a few minutes after the six songs you can play.
I had some fun with this, but not being very musically inclined, I couldn't do much with the free play time, which I think would make this a lot more fun to do over and over. Some people were complaining of lag, but not sure if it was true or they were just making a joke about why they were making mistakes. I had no problems with lag, the bad playing was all my fault!
Jumping puzzle: I love the design. I've tried it a few times and haven't gotten past the snowflake part. I'm pretty sure I'll get it eventually. However, the waiting area has piles of snowballs and you can have snowball fights with others while waiting. This is pure fun. I love this part of it. Dodging works too.
I haven't done too much in PVE yet. I opened some boxes in the outside areas the first night, wasn't too hard. I hear the little princesses (which are also in the Tixx dungeon and wonderfully creepy, I think they have no faces, they cry and cower when hit and yet they do enough damage to kill you, very twisted...great stuff). Not sure about how they work in the PVE area, but in the dungeon they seem to be ranged only. If you could round them up and put a feedback bubble on them, I would think they'd die pretty quick.
I haven't done the snowball PVP stuff yet and probably won't.
I can't say I care for the gingerbread weapon skins. Are there more skins? I haven't checked yet.
Over all, pretty happy with it so far. Looking forward to the next city when I get home later tonight.