It appears the largest benefits is embedding Lua code into TeX (found at [1] in "Programmability").

The example they present from that page:

    \documentclass{article}
    \usepackage{luacode}
    \begin{document}
    \pagestyle{empty}
    \begin{luacode*}
      function esn (n)
        return (1 + 1/n)^n
      end
      function etn (n)
        tex.print(string.format('%5d & %1.8f \\\\', n, esn(n)))
      end
    \end{luacode*}

    Convergence to $e$:

    \begin{tabular}{ll}
    \rule[-2mm]{0pt}{4mm}$n$ & $(1 + \frac{1}{n})^n$ \\
    \hline
    \luadirect{
      for n = 10, 110, 10 do
        tex.print(etn(n))
      end
    }
    \hline
    \end{tabular}

    \end{document}

which allows a pretty table to be printed in the document.