Mike,
I'm afraid this is still not possible in PPT 2007. But maybe see here if you
want to display text on top of the video:
http://www.pfcmedia.com/closedcaption.htm

Hi As Luc says you can't. You can get text in front of Video either with
Austib's methos (see Luc's link) or by adding the text into the video with
movie maker 2 (which comes with Windows XP)

There's a short tutorial to get you started here

-- http://www.technologytrish.co.uk/ppttipshome.html (in the video section)

and we are working on a more detailed tutorial which will appear on the
PowerPoint alchemy site, visit and sign up for a newsletter if you're
interested.
--------------------------------------------
Amazing PPT Hints, Tips and Tutorials-http://www.PPTAlchemy.co.uk

email john AT technologytrish.co.uk

I have needed this many times as well.

The best option, which I use on many projects, is using OfficeFX
(www.instanteffects.com). It was developed to use 3D motion graphics, but
provided your computer is powerful enough, they have added lots of video
background tools.

So the positive is - it will accomplish pretty much any needed video
background, or integrated video effects.
Bad side - costs more than PowerPoint, need a really good computer.