The significant change is contained in this new paragraph:
"For decimal numbers, specify the value with a dot rather than a comma" (for example, 4.4 instead of 4,4).
Content attributes in Microdata and RDFa can be used to override visible content.
That way, you can display whatever style convention you want to the user while meeting the dot requirement for structured data.
For example: span content="4.4">4.4 stars/span>