[Tex/LaTex] Spread bullet points across block in slide using beamer

Question

I'm using beamer to create some slides for a presentation. I've got a block containing a bulleted list. The list only has three items, and all three items are bunched up in a small block at the top of the slide.

Is there a way to spread the bullets vertically, so that the block expands to take up the whole slide, and the bullet points are equally spaced down the slide?

Minimal example:

\documentclass[t]{beamer}

\usecolortheme{rose}

\title[Review of EpiSimS for Pandemic Flu]{Review of\\ \emph{EpiSimS Simulation of a Multi-Component Strategy for Pandemic Influenza}}
\author{Robin Wilson}
\institute{ICSS}
\date{\today}

\begin{document} 
\begin{frame}{Why this paper?}
    \begin{block}{Reasons}
    \begin{itemize}
        \vfill\item Agent-based modelling is a \textbf{growing field}
        \vfill\item Pandemic Flu is a \textbf{major threat}
        \vfill\item EpiSimS is one of the most \textbf{recent}, most \textbf{sophisticated} ABMs
    \end{itemize}
    \end{block}
\end{frame}
\end{document}

Answer 1

A sort of nasty hack would be

\begin{frame}{Why this paper?}
    \begin{block}{Reasons}
       \vbox to .6\vsize{
           \begin{itemize}
               \vfill\item Agent-based modelling is a \textbf{growing field}
               \vfill\item Pandemic Flu is a \textbf{major threat}
               \vfill\item EpiSimS is one of the most \textbf{recent}, most \textbf{sophisticated} ABMs
           \end{itemize}
        }
    \end{block} 
\end{frame}