I gave four stars. I'm quite impressed with the implementation of such a such new dynamic into the game. The Statesman's TF sounds really impressive, but I haven't had time to try it yet.
There are just two issues that held it back from 5 stars, IMO.
1. The economic surge. My character was dead broke, but after the first day in the consignment house, I walked away with three million influence. One piece of salvage alone sold for 2 million influence. Partially, this due to a market surge for something new. This isn't really an expansion problem more than influence rich players over saturating the market. Hopefully the market will settle down after a month or so.
2. No new (lower than level 50) adventures. Although I've not heard one bad review of the STF, I would've liked that a few new story arcs were added.
Apart from those two (relatively minor) points, Cryptic did a great job. Take a bow devs! *applause*