I don't have too much experience in working with unit testing, the fact that I'm just a newbie in this field. I tried JUnit a little, then TestNG. I prefer TestNG 'cause it has many rich features when comparing with JUnit 3.8.x as well as JUnit 4.0. But the thing I really dignify is the way Cedric, Alex and others contribute for it. Also anytime you need supporting, they will help you with all one's heart.
I would like to say "Thanks" to Cedric, Alex and others who contributes for TestNG.
Please vote for TestNG at dev2dev!
(Sorry for my English, it's terrible)