Yes, the OS does look very nice. I'll see how it actually performs in the real world before I pass judgment.
QNX is a proven OS for almost 30 years in the industry. It's not only used in cars, routers but especially in mission critical systems like airplanes or even the space shuttle.
The big advantage of QNX over iOS' BSD kernel is that QNX is a realtime OS (with the neutrino kernel). With QNX even under heavy CPU load you still have very low *guaranteed* response times to user input while on a non realtime OS like iOS the user interface messaging system just doesn't respond at all or very late. Also QNX is fully POSIX compatible so porting apps is very easy and ultra fast.
If you ask any professional developer why he has chosen QNX his answer is probably: architecture and reliability. QNX is one of the best mobile system OS out there. I'm really impressed that RIM has chosen to buy QNX and use it for their tablet.