<small> element - changes from HTML4
This element is one of the presentational elements including
<b> which although previously
virtually discarded in favour of CSS styles have now been retained and redefined in HTML5.
In HTML4 the
<small> element provided a means to display text in a smaller font with no additional meaning conveyed. In HTML5 this element should now be used to
indicate that the text it contains is what is commonly referred to as "the small print" or "the fine print" in a written document.
An example of this is the section listing the terms, conditions and disclaimers in a user contract which are often written in smaller type than the main body of the document.
This seems a logical definition for this element giving it a proper meaning and a justified place in HTML.