I have a site with over 9,000 pages. Most of them are on wordpress, but a few old pages are still in HTML. Moving my site to a new host was an arduous task and after the move all of the wordpress pages -- which are the bulk of the site vanished from Google's index. For some reason the HTML pages are there. The wordpress pages and index page continue to get natural links everyday and I never tried any blackhat SEO. Has this happened to anyone before? What can I do about it?