Very Good. InDesign CS has an impressive set of AppleScript commands for laying out graphics, navigating your documents, fine-tuning your text, and much more.
QuarkXPress
$950
www.quark.com/products/xpress/
Good. QuarkXPress is a mainstay of the printing world, but its AppleScript dictionary isn't quite as comprehensive as InDesign's. For example, QuarkXPress can't automate adding Web links to your layout files like InDesign can.
Best choice for AppleScript: InDesign CS. Check out www.adobe.com/products/indesign/pdfs/indesign_cs_scripting_guide.pdf for a thorough guide to scripting InDesign to the fullest.