With Steve Ballmer announcing that Microsoft is going after Ad revenues aggressively and to directly take Google head on. Global Ad business in Digital world is around 650B USD. That justifies their investment in Facebook, a social networking site, at a 15B USD valuation.

Looking at India and China, the growth story is similar in the Digital and Mobile world.

China View reports

Strong advertising sales boosted Chinese portal Sina.com’s third quarter earnings 61 percent which helped offset a decline in wireless services revenue. The strong growth in ad sales was fueled by a sharp rise in financial service ads and the portal’s commercializing bloggers’ space has also contributed to the sterling results.

Net income hit 17.2 million U.S. dollars, or 28 U.S. cents per diluted share, compared to 10.7 million dollars, or 19 U.S. cents per share, in the same period last year. Revenues grew 15 percent to 64.3 million dollars, Shanghai-based Sina Corp said in a statement Thursday.

Sina, China’s largest portal, is relying increasingly heavily on ad sales as the non-ad business shrank in the quarter, mostly due to a decline in mobile value added services as a result of a tougher regulatory environment.

Ad revenue swelled 40 percent in the quarter to 45.8 million dollars, while non-ad sales fell 21 percent to 18.5 million dollars, which met company guidance.