The Oldham riot was sparked by a clearly racist attack on a white pensioner by Asian youths, again showing that racism isn't the sole property of one group. There is a lack of integration in these areas, because immigrants aren't encouraged to integrate.
Burnley, which is a very poor area (40% unemployment IIRC), is a good case of tensions being caused by one group getting favourable treatment, because the council was spending money on a predominently Asian council estate. There were two large council estates, one white and the other Asian.
Multiculturalism's failure in Canada hasn't manifested itself in things like race riots or serious crime problems, but in the above-mentioned governance problems and polarisation of the federal political scene since the 1993 election. The Reform Party (which later became the Canadian Alliance, which merged with the Tories) was born out of the western provinces' disenchantment with Ottawa's policies, because they felt they weren't being given a fair go. They didn't want the idea of multiculturalism or "distinct societies" and wanted all Canada's provinces to be treated equally. On the other hand you have the Bloc Quebecois, whose goals are pretty obvious, which actually became the official opposition in 1993 because they won most of Quebec's seats. Both gained ground at the expense of the Tories.
This has been cited as one of the main reasons the Liberals have been able to win four terms in office despite the majority of Canadians not voting for them (and haven't done so since 1968).
Well, two years later they had the referrendum in Quebec, and the "non" vote barely won out because the minority of Quebeckers who weren't Francophones (e.g. Anglos, ethnics and aboriginals) almost solidly voted "non". You also had that comment from the then premier of Quebec, Jaques Parizeau about the sort of votes which got the "oui" proposition defeated.
If that isn't a reflection of a divided society, then what is it? That has to be the as damning an indictment of multiculturalism as any.