PowerPoint 2007 vs Impress 3.2 vs Keynote vs Beamer

[jbutton]

What are you thoughts?  PowerPoint 2007 has great charts integration and some nice theme.  Impress 3.2 looks more like PowerPoint 2003.  And Keynote is superior in rendering and animation.  Beamer is great for scientific presentation and complex math equations.   I often use Impress because it is what comes with Linux.  But sometimes I use PowerPoint 2007 because it has nice theme and I need nice charts.  Beamer is very tempting but editing beamer is hard work.