[Tex/LaTex] Uncovering items with changing bullet color

Question

In this case consecutive items get covered. How could I change this behaviour so that all items would be black and only bullets would get different colours?

\documentclass{beamer}
\setbeamercovered{transparent}

\begin{document}

\begin{frame}
\frametitle{Title}
\begin{itemize}
 \item<1-> First
 \item<2-> Second
 \item<3-> Third
\end{itemize}
\end{frame}

\end{document}

Answer 1

My answer, adapted from the example in the Beamer user guide, p82:

 \documentclass{beamer}

\def\colorize<#1>{%
    \temporal<#1>{%
        \setbeamercolor{item}{fg=blue}%
    }{%
        \setbeamercolor{item}{fg=red}%
    }{%
        \setbeamercolor{item}{fg=blue}%
    }
}

\setbeamertemplate{itemize item}[triangle]

\begin{document}

\begin{frame}
\frametitle{Title}
\begin{itemize}
 \colorize<1> \item First
    \begin{itemize}
        \colorize<2> \item First a
        \colorize<3> \item First b
    \end{itemize}
 \colorize<4> \item Second
 \colorize<5> \item Third 
\end{itemize}

There must be a better way of doing it though. Does anyone know how to redefine \item so as to get the desired output without having to use an extra command (\colorize here) in front of each \item?

EDIT: \colorize is now compatible with all levels of itemize environments.