CMS, HTML quality, SEO features for a 60k pages site

We run a website of about 60,000 web pages and 2 million hits on our web server (serving some 300,000 page views per day) Our 60,000 pages are a mix of hand made HTML pages (created by at least 3 or 4 different web designers with Dreamweaver only: some 30% of them) and dynamically generated pages (created by our content management system during batch nightly jobs, and stored as static HTML files afterwards, as the content doesn’t change too often and we can afford to keep a static page for months and months). In this moment we don't have full control of the manually edited pages, as the HTML is not W3C compatible, full of broken links, nested html, no attention at all to SEO technique (Title of the pages, meta tags, etc.) and all the typical problems of an handmade site. Objective of this Project is to kill the manual side of our site, allowing the web designers to use a content management system similar to the one they are already using (by customizing Joomla which should use our existing template structures and save static files instead of serving them dynamically to reduce our already-very-busy mysql), so that our company could be: - “Dreamweaver-free” after this project - Able to keep under control the HTML/CSS quality and compatibility with W3C standards - Able to take care of some SEO aspect of all the pages - Introducing authoring process by permissions with the usual roles of Joomla: author, publisher etc. Please send an email to to be invited and receive the full specs of the project. Due to the size of the project and the notorious name of our company, we'd like to keep maximum confidentiality of the project.