For the current version of LuaLaTeX, the correction of spacing after italics is broken. As a workaround, one could comment out some lines in the luatex-unicode-letters.tex as they did on TL2013.
All entries from \l 1D400 to \l 1D7CB has to be taken out.
In TL2013 this section is marked with:
% XXX: luatex math italic correction bug
The complete "corrected" .tex-file can be seen here http://tug.org/svn/texlive/trunk/Master/texmf-dist/tex/generic/config/
After changing the file, the FNDB has to be refreshed as well as a recreation of the LuaLaTeX format.
Thank your for your efforts.
PS: see http://tex.stackexchange.com/q/131717 for an example