The GOOD:
The new user interface is really decent. It will give a fresh approach for newcomers to the game. Especially the improved quest log will be what is most helpful to players, as well as the ability to quickly see their archivements.
The new world map is completely 3D-rendered, it is an accurate represetation of the game world.
You may have
two spellbars visible at once (Options->User interface). Each spellbar has up to 12 powers available, so up to 24 powers visible onscreen at a given time. As of yet, the extra powers are not reachable by keyboard shortcuts as no binding interface seems to exist.
There is a button to quickly access mounts, so they will no longer consume spellbar space.
There are now icons showing each player in your party, and these icons posess health and mana bars that update rather quickly. The updates are not instant but they do not take nearly as long as party window did before, I clocked updates at 1-2 seconds max with the laggy Amun server.
Archers do not run out of arrows. Arrow backs are bought once and equipped forever.
This drastically reduces the weight of the archer.
Some low warrior weapons have been revamped and look nice, high level players will actually be using some of them for fusion from what I've seen so far. Bows were said to be overhauled, but I could not find any changes.
Mages have a new piece of armor (Bracelets) it has quite alot to their armor points and grants them a strong defense.
The BAD:
The combat log and the chat cannot be seen at the same time. This creates problems for players who rely on this, such as Hunters who need to view tracking information. in fact, you will need to do alot of tab switching or simply not chat at all during combat. I
really dislike this.
There is some frame rate loss for some players from the new UI, sometimes up to 25% or more.
Chat above peoples heads gets cut off. This makes it very difficult to see what people are esaying without being on a chat tab. Furthermore, the chat from NPCs can no longer be made out in towns becasue it is always truncated and does not appear in any chat tab.
Moving movement updates over to the TCP protocol seems to cause alot of lag and even more severe positioning issues than before.
The UGLY:
The new user interface is too "bubbley", it makes the GUI seem childish and wastes alot of space. There is alot less room to view information than before, especially in trade , commerce and inventory dialogs. The fonts, health bars and other elements seem quirky, hard to read and out of place in some cases.
I am not impressed by premium being renamed to "Item mall". This is not an "item mall" game, and you guys better not make it into one.
The new minimap has absolutely no combat functionality.
Mages' bracelets give way too much armor. Mages wearing only level 50 braclets were ending up with more armor points than level 60 Warmaster Barbarians and yes, even Knights. They were also taking rediculously low amounts of damage; as it stands, this needs nerfing.