rutineli
You are right about the shift. The majority of labour-intensive production is mainly along the eastern seaboard area, where there is also a lot of inward investment as well as what are called SEZ (Special Economic Zones). Guangdong Province in the South East is one of the major manufacturing areas (seems to be mainly consumer durables). Liaoning Province in the North East has shipbuilding, oil and heavy industry.
Many of the 'peasants' from outside the cities and particularly from the western provinces migrate to the cities, where they work to fulfil the ever-growing demand for labour. Some provinces also have suffered the loss of traditional heavy industry under privatisation, with consequent high unemployment.
You have only to take a look at TV coverage of the huge problems caused over the Spring Festival when hundreds of thousands of migrant workers were stranded at railway stations (approximately 800,000 at Guangzhou East Railway station alone) to see how vast the scale of migration is. However, remember that the population of the country is 1.3 billon, with a labour force of almost 800 million (I think).