I use it and like it. I haven't done any detailed testing, but if shoot the same subject with Camera/HDR and a different app, like Clear Cam, that doesn't use HDR, there's a perceptible difference that usually comes out in Camera's favor.
TrueHDR and Pro HDR are better if you really want the whole HDR experience, and other apps are better if (like me) your hands tend to be unsteady while holding the camera. I like having a lot of choices.
Lately I've been using Hipstamatic most of the time, but I guess that's a different subject.