Last year I made absolutely sure that the NT server hosting my site had the FP extensions. I wanted the "ease" of updating my site available to me. However, I ended up doing all the updating locally, then FTPing the final pages to the server manually, instead of letting the FP97 wizard do it. Guess what? AltaVista correctly read my description meta tag, and searching for my pages with keywords worked beautifully. It seemed all the other deep search engines also were able to index my site, metas and all. I even posted my results on this site, and asked why it worked: the answer I got was because I transferred my pages manually (FTP) instead of using the FP97 wizard.
To this day, changes I make to my metas, keywords or titles (now using FP98) are correctly seen by the search engines. In fact, by using search engines I've found several discontinued pages still being indexed by the 'bots because I missed deleting a single link to that page from some other page.
So if you must use FrontPage, *don't* utilize the convenient FP extensions to update your site. Just use a regular FTP client and post each page individually. It works for me...