The 'Mid-to-Mega 20th Annual Wealth Creation Study (2010-2015)' by Raamdeo Agrawal analyzes economic data, company financials, and stock prices to identify top wealth creators in India. TCS, ITC, and HDFC Bank are highlighted as the biggest wealth creators, while the report emphasizes the shift in wealth from public sector undertakings (PSUs) to private companies across various sectors. The study concludes with a focus on growth characteristics necessary for transitioning companies from mid to mega status in the market.