NW has quite a few good plot hooks and does a nice job identifying some interesting areas of Neverwinter.
The race expansions are mostly fluff, IMO.
Included the Bladesinger class, no opinion yet, but it has its own thread.
Themes are interesting and represent power creep in the game, so everyone will want a theme eventually, if their GM allows. Themes offer an excellent opportunity for WoTC to sell books. That being said not all themes are created equally. This was discussed on other threads. Also the themes presented, may not support all non-essential races well, though GM could open these up. In some cases themes seem to duplicate racial powers, eg. when your shifter is shifting, he can also form into a hybrid form and be doubly shifting. I have to look more closely to see if the bonuses for my shifter shiftily shifting stack or not.
The Dead Rats and supporting wererat fluff and crunch are excellent and IMO very useable (possibly more so as a GM).
Some themes are much more potent in combat with eg attacks or poison resistance. OTOH, the Oghma theme may be helpful for role-playing but does not deliver at all for combat purposes, nor does it improve much at higher levels. Hopefully your GM will give you some additional rituals or no component costs if you take this one.
I do look forward to more themes, but hope that they will be more balanced in the future.
I like the creatures, they are somewhat spread out, IIRC, amongst organizations and plots. The personalities and creatures are all in the heroic tier which is great in providing weaker varieties of some interesting critters, yet at the same time it would have been nice for some paragon statted creatures. Again, it does a good job identifying hooks for potentially conflicting groups.
Still reviewing it, but that's my first impressions. Hope they were useful.
