<!-- a bunch of extra stuff before this -->
Other stuff I don't care about
<!-- a bunch of extra stuff after this -->
jQuery's :contains() selector would do this.
For your specific example:
$( "td:contains('Keyword: ')" ).next().contents().val();
First it finds that contains "Keyword: ". Then it finds the next element, then it splits that into an array of parts, then it selects the first element in that array, then gets the value of that element.