In the poll this morning (UTC) the average year for the mainstreaming of the internet was 1996. This also being the year I chose.
It looks very much like I was popular, and wrong.a_pawson went digging through the ONS
to see what the takeup figures were:
%age of households with internet acccess:
1998 - 9
1999 - 20
2000 - 34
2001 - 39
2002 - 45
2003 - 49
2004 - 51
2005 - 55
2006 - 57
2007 - 61
2008 - 65
Which means that even if you take 40% as mainstreaming you're not there until the end of 2001, _after_ the DotCom Bubble had burst.
Obviously, people were using it from offices before then, but even so, it looks like the wave rolled over the general public later than I thought.