I've spend some time last week writing up the documentation for a first
footnote package and just a couple of minutes ago added it to the experimental
code section on the project www server

you'll find it at

 ftp//:www.latex-project.org/code/experimental/xfootnote.tgz  (tar gzip)
 http//:www.latex-project.org/code/experimental/xfootnote      (dir with
                                                              individual files)

it consist of a package file xfootnote.dtx (roughly 20 pages)
a docstrip batch file xfootnote.ins and a small test file xfootnote-test.tex

so far it only covers latex like types of footnotes, other layouts need
adding. so you will not be surprised if i have essentially the same questions
as with the xcontents stuff:

 - do you think the templates provide you with the keys to implement the
   layouts people might need/want?

 - what is missing, what is wrong, what is right?

 - there are a lot of questions posed in the .dtx file, perhaps some of you
   have some answers?

 - if anybody thinks he/she knows of designs that can't be achieved i would
   like to learn about them --- there must be many i'm sure ...

best
frank