I wonder if Andy is reading this? Possibly there are other people around who are also interested in this. I think the HAT people at NHC headquarters are also interested in these things. There once was talk of starting a debugging group for Haskell, but I don't know what happened.

There's a mailing list for debugger-related discussion at debuggers@haskell.org (subscribe in the usual way). To date it has received a single message, namely the nhc 1.06 announcement :-) Cheers, Simon