Flattening the comments and form fields in a PDF file is an important step for many users, to prevent further modification and to archive copies for legal reasons. Adobe Acrobat can flatten everything - all forms, comments, links, the lot - but it can't selectively flatten only certain types of comment, or selected page ranges. Until now.
We're giving away a scripted add-on tool for Acrobat (7+) which can flatten comments by type, with or without forms included, and over a subset of pages you specify. It's written in JavaScript and will work on both Mac and Windows installations, plus it's covered by a Creative Commons license so you can modify it for your own needs.