Frank Duncan has been working on Nekthuth, a solution to the problem of programming in Lisp using the vim editor that I complained about previously. So far Nekthuth only works with SBCL and it lacks most of the features in SLIME, but it is a start.
Of course, we've heard the promise of a solution before only to be disappointed, so I'm still glad I went through the pain of switching to Emacs. Unfortunately, the architecture of vim makes it difficult to build a SLIME-like solution, so Frank's achievement is all the more striking. If you absolutely, positively can't give up vim but need to program in Lisp, you should give it a try.