There is already a load of awesome stuff in the new edition of JDRPG but still screaming out for supplements and articles as only so much can be crammed into a book and keep the price down (take a look at Ptlous if you don't know what I mean 700+pages and a dvd with more or less the same on it for over 100 bucks).
I did a fair bit of work on a Luna-1 sourcebook for the old D20 version of the game, but it never really got anywhere and is knocking around a disc somewhere I think, though I may just start again from scratch with that if I ever get around to it.
Adventures are always great fun to write and even better to play as Mega-City One is such an awesome playground and full of ideas that the city itself becomes a character so more adventures are a must.
The Cursed Earth hasn't really been covered that much in the past (Hotdog Run didn't make it into the last book, though was hosted on Dredd Times till my site got pulled by the server and I lost the backups) and a few articles in back issues of S&P. There is a wealth of oppertunity for anyone wanting to address this and get their fingers clicking on the keyboards
I would love to see more Crazes and was working on a second crazes book before D20 got discontinued so who knows lol.
As it stands the new rule book is about all you need to play Judge Dredd, even if you are brand new to the character and his universe, Lawrence did an awesome job and the editing and layout are perhaps the best I have seen from Mongoose in a very long time so kudos all round.
Marc