Extracting zip does not store files in "today" in Finder
By unzipping the archive you did not modify any file or folder in it, hence the original creation and modification times are used.

In your example the Finder only sees "7 October 2009" as modification date for jquery-form-validate.

The only way to achieve what you want is to use a tool that updates all the modification times when unzipping.

In the terminal you could (untested)

$ find jquery-form-validate -exec touch {} \;