Redefining commands in a new environment

Question

Two questions:

1. Does LaTeX allow one to (re)define commands within a \\newenvironment? I\'ve tried using \\renewcommand, \\newcom

Answer 1

Too late perhaps, but it may be useful for someone else

\newenvironment{coolitemize}{%
\let\olditem\item% 
\renewcommand\item[2][]{\olditem \textbf{##1}\\[0.3\baselineskip]##2}%
\begin{itemize}}{\end{itemize}%
}

and use it

\begin{coolitemize}
\item[Title of my first item] Text of my 1st item.
\item[Second one] And some text here.
\end{coolitemize}