I've been playing around with the float placement options in ConTeXt, but I could find no way to enable "float pages".  If you're not familiar with float pages, here's a quick blurb:

"If there are too many floats to fit on a page, LaTeX pushes them on to the next page, and the next; eventually, floats may end up at the end of the document. If the [p] option has been provided to individual figures and tables, they may be pushed together onto a “float page” that has no text." - http://mintaka.sdsu.edu/GF/bibliog/latex/floats.html

I'm not interested in using \setupfloat[figure][default=page].  It forces all figures to a float page with one picture per page.  In latex, the behavior that I desire can be specified with:

\begin{figure}[htbp]
  \includegraphics[width=5.0in, height=3.0in]{myfile.jpg}
  \caption{Blah}
\end{figure}

Cheers,
Mike