\mode<presentation>

\setbeamertemplate{itemize item}[triangle]
\setbeamertemplate{itemize subitem}[triangle]
\setbeamertemplate{itemize subsubitem}[triangle]
\setbeamertemplate{section in toc}{$\bullet$\hskip.5em\inserttocsection}
%\setbeamertemplate{subsection in toc}{}
\setbeamertemplate{subsubsection in toc}{}

\mode
<all>
