These are the two best threads from Clintonn which will give you all the deep insights on quant scoring
http://www.www.urch.com/forums/gmat-problem-solving/54297-just-finished-another-gmatprep-quant.html (very good discussion here and inputs)
http://www.www.urch.com/forums/gmat-problem-solving/53548-got-50-quant-gprep-six-incorrect.html
Hope that helps you and others as well ;)
I have read that news on TOI and it's one of the crappiest news I've ever read. I thought of writing to the chief editor of the TOI to not to allow such poor quality news figuring up in their newspaper. It looks like the writer of the article doesn't even know ABC of GMAT. Please don't buy this article.
I also read about the book here
Amazon.com: The Official Guide for GMAT Review: Graduate Management Admission Council (GMAC): Books
Supposed to be released by 16 march ;)