just tryied netbeans and it looks cool :_)
is it well supported within the C community?
uhm... I don't really know about support within the C community. I've been using it for C/C++ for probably 4 or 5 years. They constantly update the C/C++ language plugin. When I was doing just pure linux stuff I used KDevelop, but ended up needing and IDE that ran on multiple OS's. I tried eclipse first - at the time it's C/C++ parsing engine was painfully slow - I think it's gotten better. The Netbeans parser at the time was really fast compared to eclipse, so I chose netbeans. They have had a few releases where the parser has gotten worse, but it's current state is pretty dang good - and since I am now accustomed to all the keyboard shortcuts, it feels way to familiar to start switching again.
One thing I really like about netbeans is it's ability to import a makefile based project. Where I work, everyone uses a different editor/IDE, so we use the least common denominator of makefile projects. With netbeans, I can check out the source from CVS (yes we still use cvs), and do the import into a netbeans project with just a few clicks. Eclipse is a real pain in the ass when it comes to doing the same import.
KDevelop was pretty good for doing the import also. I used it back in the version 3.x era - they were getting that IDE to a point that it was pretty good and feature rich - just needed a bit more work to get it to be a great IDE. At that point they decided to throw everything away and start from scratch. I've tried version 4.x, and it's fairly solid, but since they decided to start from scratch, they lost a lot of features that will take years to put back.