I had a look at the poll results at an organisation called YouGov. They make for interesting reading. Here are some selected statistics, the links are in PDF format.
In a Poll on the 11th of February 2005 (yesterday). Only a third of respondents thought Charles should be the head of the Church of England with a majority against. 7% thought that Mrs Parker-Bowles should be queen - down from 15% in a previous poll, even though the media operation of the establishment has been in full swing.
Only 8% of respondents thought the marriage of Charles and Mrs Parker-Bowles would strengthen the Monarchy, (maybe the 7-8% were just saying yes to everything to make the researcher to go away).
Only 14% of people thought the monarchy set a good example of moral standards. According to yet another poll, only 26% of people believed there would be a monarchy in 100 years time.