Would it matter if it had?
As a 'born and bred' Londoner, I have noticed a change in the ethnic population of my home city. When I was younger, the area I was from (North London) had a large ethnic Greek Cypriot population, next door to a large large Jewish community, a large Irish population, and lots of Italians (the last two groups including members of my family). As the years have passed there has been a gradual move to increased numbers of Turks, Turkish Kurds and Poles, although the Jewish, Italian and Irish have remained fairly constant.
In terms of actual skin colour, without sounding too Guardian-reader about things, I genuinely haven't noticed any change, though according to my mum it certainly has over the past 50 years. But over the last 30....not up here. I believe it may have done in parts of south London but if you really want to know if it genuinely has then you need to look at census reports, not listen to what people think, as what people think they see is often wrong. Census returns are available somewhere on the internet.
There has always been immigration to the UK. This
is an excellent book which outlines the history.
We won't know until the next census if other nationalities are really growing in number to the extent that some people think. Immigrants certainly are growing in number, but not to the extent of outnumbering the 'natives'.
As an aside....I went to my usual Burns' Night party on Sunday, with a friend who is engaged to a Polish girl. Last year, she had about 10 Polish friends and family there. As of Sunday, most of them had gone home due to the economic downturn. I would guess that many more will follow.
Vicky