In the last 15 months I use insight (came with FC6). It is not great, it is written in Tcl/Tk, but it is simple and useful. DDD is of similar quality / utility, but somewhat harder to use (various GUI gotchas and omissions). I also tried to integrate gdb with my IDE, SlickEdit. It worked OK (I played some 4 hours with it), but I did not like the GUI context switches. I like my IDE to remain unchanged while I am debugging; on Windows I use SlickEdit for IDE and Visual Studio Debugger for debugging. So from the 3: Insight, DDD and SlickEdit, Insight is my 1st choice, I use it >95% of the time, command-line gdb and DDD make up the other 5%. If I get the chance, I will eval Eclipse at some point, my work PC does not seem to have enough RAM (1GB only) to run Eclipse reasonably well.
I have also heard a lot of praise for TotalView, including 1st hand during a job interview. I obtained an eval for our company in late 2008, but in the end we did not proceed as gdb was good enough for our needs; and it is free and ubiquitous.
