Hi Jan,
I agree with you that the wording on the LuaTeX page (IMO on many TeX related
pages) is mostly understandable only if you already know exactly what TeX or
LaTeX/ConTeXt is.
A more general LuaTeX page would be needed ("LuaTeX solves your typesetting
problems. Just download texlive and get started..."). But there will be voices
that say "well, it's not related to LuaTeX, but also to PDFTeX and Knuth TeX
and ...". So, a more general TeX page would be needed as well. I don't know
where to start. It would take a lot of effort to make a good website for the
non-TeX people explaining what TeX is about and so on.
This might be something for the user groups (TUG, UK-TUG, DANTE,...).
Patrick