For what its worth, I find the current binding for M-, extremely useful - having it right next to M-. is very intuitive (I didn't even know about the M-* binding). It also corresponds to bindings in the usual C/C++ modes.
In the course of looking up M-* in the document I noticed it wasn't there. Actually, it was there but rendered incorrectly: I discovered that , doesn't escape commas in texinfo, and you have to use something like @comma{} instead.
Will I was at it, I also made sure there were placeholders for all the as yet undocumented functions in the function index, but commented them out so they don't appear in the index. Those who are in a better position to document these functions can do so as time permits, add the appropriate anchor for the index link and uncomment the function in the index. It serves as a useful reminder of what functions still need to be documented.
I committed the modified doc/slime.texi into CVS.
Regards,
-Jeff