Have you ever used iFilters for PDF in MOSS? It's beautiful. You may simply download it from adobe website and install it on the MOSS Server and enjoy the enterprise content search for the PDF content. Such a sweet component becomes a pain once you'd like to upgrade to 64 bit platform, simply because  adobe iFilter it doesn't have 64 bit support.
 Last week I found Foxit PDF iFilter. It is not a free product, but $1184.93 doesn't look like an issue for a huge enterprise with 64 bit implementation of MOSS. I haven't tried it yet myself, so if you have used it before send me your feedback.

Cheers
Alireza