There is also Saving Powerpoint presentations as web pages which might get you some ideas.

Good luck, MS seems to have kept the .ppt stuff pretty close to the vest.

You can download the ppt specs at http://www.wotsit.org (search for "ppt").

The document is a zipped html directory.

Appendix 3 is specially interesting: "Sample code to read the text out of a PowerPoint '97 presentation." (in C++)

If you make a Perl version of this, it would be nice if you could submit it to CPAN!

Well so far, I've managed to do easy things thanks to the MSDN such as adding slides (where and which exact type) and drawing text areas, shapes, labels... However, I can't seem to add text : one of the VB syntaxes (there's several ways apparently) MS provides is the following :
Set oTitle = ActivePresentation.Slides(2).Objects.Title
This would be the VB code (according to MSDS). I assume the perl code would be :
$ppt->ActivePresentation->Objects->Slides($nb)->Title->Text = "TaGaDa"
where $ppt is
$ppt = Win32::OLE->GetActiveObject(MSPPT.'.Application') and works just fine.
However, Perl doesn't seem to know what objects. is and returns the following error :
Can't call method "Slides" on an undefined value at D:\source\powerpoint.pl line 23.
MSDSN reference is here :
http://www.msdn.microsoft.com/library/en-us/dnpower97/html/ppppt_w95.asp?frame=true#ppppt_w95_work

If u have any idea, let me know, thanks !!!

You can use "QueryObjectType" for debugging.
Print the object type for "$ppt", and the object type of "$ppt->ActivePresentation" and check if they are what you expected.

Win32::OLE->QueryObjectType(OBJECT) 
   The QueryObjectType() class method returns a list 
   of the type library name and the objects class name. 
   In a scalar context it returns the class name only. 
   It returns undef when the type information is not 
   available.
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