New Form Features in HTML5
HTML5 includes many new features to make web forms a lot easier to write, and a lot more powerful and consistent across the Web. Opera is sharing article that gives a brief overview of some of the new form controls and functionalities that have been introduced. The article includes new form controls, new form attributes, new output mechanisms, validation, styling with CSS3, and cross browser compatibility.
To illustrate some of the new features, the article comes with a basic HTML5 forms example. Note: the look and feel of the new form controls and validation messages differs from brower to browser, so styling your forms to look reasonably consistent across browsers will still need careful consideration.
Source: http://dev.opera.com/articles/view/new-form-features-in-HTML5