Q: What's the most important feature a unit testing framework for Java needs to have in order to become mainstream?
(I'm only 27% joking, by the way...)
Congratulations to Cedric and Alexandru!
No, it doesn't make the framework inferior. Just less likely to reach a mainstream status.
For example, if you write an IDE plugin for IDEA, your plugin's theoretical user base limit is that of IDEA users in general. If you write an IDE plugin for Eclipse, the same applies -- except that Eclipse's user base is quite probably hundreds if not thousands of times larger simply because it's free of charge.
Now, the best approach is obviously to structure your plugin in such a way that it's as easy as possible to support both IDE's simultaneously ;)
You're missing my point, Kishore.
I'm not arguing that having a plugin for IDE X would make a unit testing framework any better/worse as a unit testing framework.
I'm arguing that, today, in order for a unit testing framework to become mainstream (a la JUnit), it has to be integrated into mainstream IDE's such as Eclipse.
If none of the unit testing frameworks for Java would have an Eclipse/IDEA/JBuilder/etc plugin, the situation would obviously be different.