I don't plan to defend the NX, nor invest in its lenses (though the 30 was tempting). But i did compare one of its lower reps, the NX100, vs. the 'enthusiast' camera world. In the 100-400 ISO it's a world class (see prior definition of 'world'), particularly in raw. And up to ISO 800 my old NX100 holds quite well... alas, against the original 5D and NEX-5N. Even its often blamed JPG engine is not so hopeless as believed.
NX100 w/ various Nikkor manual lenses
https://picasaweb.google.com/107634715157732050217/SpringFlowersAbstractMacro
or w/ the 20-50 kit lens
https://picasaweb.google.com/104896643939448365565/OurVeryBestSwissFall
Surely i'd like a full-frame not larger than the NX200, w/ cleaner higher ISO and 1K+ shots per charge... but meanwhile i use all my glass on the NX100 and work w/ its limitations. Samsung's roadmap would only be of concern if i were to invest in their glass, which despite the promise, i can't commit. So i keep buying canikon glass and use it on NX and other CSC's via adapters.