\documentclass{beamer}
\usepackage{beamerthemesplit}
\title{Presentation that advances slides automatically every 2 secs (switch to presentation mode)}
\author{Volker Mische}
\date{23.~February~2010}

\begin{document}
\frame{
\hypersetup{pdfpageduration=2}
\titlepage
}

\begin{frame}
\hypersetup{pdfpageduration=2}
Hello World! 1
\end{frame}

\begin{frame}
\hypersetup{pdfpageduration=2}
Hello World! 2
\end{frame}

\begin{frame}
\hypersetup{pdfpageduration=2}
Hello World! 3
\end{frame}
\end{document}