Who is holding back the world economy?

The western media is rife with reports denigrating the Chinese economy. But in November, the International Monetary Fund upgraded China's real GDP growth from 5% to 5.4% for this year. It also predicted China's economy to be on track to meet its growth target. Meanwhile, the G7 economic block looks like it's in need of urgent attention if not action. The OECD estimates the block's quarter-on-quarter growth to be three fifth of a percent in Q3. Why are they not contributing more to global growth? Why are some in the Western media so fixated on China?