Keynote is cheaper ($20 in the crappstore).
Keynote looks incredible.
Keynote is way more expansive.
Keynote doesn't try to get you with the HD bullshit.
This isn't even worth downloading to try, go get Keynote.
And if you're not up for a precise and beautiful show, iMovie does the job as well.
Quick note, look at the play button in the icon - windows port much? Stop invading the Mac community, please. We prefer quality software.