Lacks content, Devs seem clueless.
Once you get up to the mid 20's and upward, you'll find a serious content gap, running out of missions. Wouldn't be so bad, except mob xp is negligible, so grinding open quests is the only thing to do, over and over until you open another contact.
Also with the content, there are only enough missions in game so that you have to do all of them to level, so every character will do all the same missions in roughly the same order. Since all the power combinations play pretty similar, rolling alts also gets old fast.
The sounds, are mostly recycled from CoX, some are even the exact same sounds.
Currently, the biggest flaw of the game is a severe lack of content. Given that even casual players have been hitting 30 (out of 40) before the headstart was over, they better get some content patched ASAP.
Another problem I personally have is that there are next to no instanced "dungeons" in the game, with the first Lairs coming around level 28-32, and only a few of them, very short. Most missions are the standard go to circle indicated on the map and kill X of Y, click on X of Y, or kill X. You can literally be doing the same mission with different mobs over and over and over. Occasionally, you get an instanced mission, but these are easily completed solo, in under five minutes.
Bringing me to my last point. The game is really solo oriented. You can team, but it's not necessary, and even counter productive to do so. With all the open world spawn camping you have to do (EQ anyone?) to complete missions, and everyone doing the same missions, and everyone running solo since it's faster, you find kill/clicky stealers always swooping in to take it while you fight surrounding mobs, etc. It leads to much bad feelings among players.
The travel powers can also make teaming a hassle, since if you are on a team of fliers for example, and you have Acrobatics, the mission will be completed by the time you reach the team, or you'll get killed on the way, since you can't avoid them. Tunnelers with missions on top of a building..etc. Lots of disparity there.
It's an MMO-lite, probably a 100,000 base after things settle, but it introduces nothing new to CoX players except less content and updated graphics.
That said, it's worth a month's play.
EDIT: This was prior to the day 1 mega-nerfs across the board. The final nail in the coffin for me personally. Avoid this one for a few months until some devs get rightfully fired for incompetence.