Stealthbot still works, it's just not actively developed. You can use any login/password and it will authenticate for you.
Here is the updated information on obtaining and using stealthbot:
http://forge.isxgames.com/projects/stealthbot/knowledgebase/articles/5
Also, Cybertech has access to the Stealthbot code and I'm sure if it ever "broke", he could easily make enough changes to it to have it working again, etc. So, while you may never get any new features while Stealthy is currently away from the game, I think it will most likely continue to work (as it is) as long as ISXEVE works.
(By the way, ISXEVE got quite a few new features this past year that very few scripts have taken advantage of. I have a couple of new script writers that are actively working on new bots and I think they may come out in the next few months.)