To answer some points in this thread, some interesting stats from an LSE study:
cep.lse.ac.uk/pubs/download/ea006.pdf
The UK has a lower share of immigrants in its total population (10.2%) than Australia (25%), Germany (12.9%) or the United States (13.6%).
Immigrants, on average, are less likely to be in social housing than people born in the UK, even when the immigrant is from a developing country.
There are potential economic benefits associated with migration, especially to fill gaps in the UK labour market ? where there are shortages of workers, whether highor low-skilled. While there may be costs to particular groups, there is little evidence of an overall negative impact on jobs or wages.
Many new immigrants ? those who have been in the country for less than a year ? are not primarily from the poorest countries, but from developed countries or wealthier emerging countries like South Africa.
Unlike in the United States, where the skill composition of immigrants is tilted towards the unskilled, the skill composition of immigrants to the UK is more biased towards skilled workers.
A recent study of the fiscal impact of immigration of workers from the eight EU accession countries of Central and Eastern Europe (the A8) concludes that because this group of immigrants are more likely to be in work and make less use of welfare and other public services, their net contribution is positive.
Nevertheless, there may be some downward pressure in the low wage labour market where (despite their higher relative education levels) many new immigrants tend to find work.
There has been some concern that rising immigration puts extra pressure on schools and on the housing market. These are areas in which there is still little hard evidence.