Uh... Did I miss the part where he explained what was wrong with existing clients?  Without a clear, specific problem to solve, this is going to be an exercise in wasted time.<p>I was looking over the mailing list and just about everything I see mentioned can be done with Mutt (or Sup).  Personally, I use gnus on emacs.  Add in some org-mode magic and you have just about everything anyone could ask for (well, search is not as nice as I'd like it).