I implement Drupal, WordPress or Get-Simple on all projects for two reason; a client can update or edit their website anywhere they have an internet connection. Content management systems provide the flexibility of expansion without the client every having to edit one line of code.
HTML5 / XHTML
I currently use HTML5 for most of my projects. However, I can also develop projects in XHTML for clients that want to be accessible to much older browsers.
For projects that are at least twenty pages or more, I implement WordPress. This is a platform that almost any user can grasp with some minor training. It is scalable and offers a plethora of features.
This platform is for projects that are under 20 pages. It is light-weight, easy to use, offers CMS (content management system) features without the use of a database and is very portable.
This platform is for large complex projects that has very specific needs.