Ipsos Reed is a major Canadian polling company. This was done in conjunction with a division of Canadian Press.

- 4 in 10 online Canadians have read a blog at least once (42%)

- 58% believe blogs influence public opinion

- 4 in 10 believe they influence media (45%)

- 41% believe blogs influence politics and public policy

- 4 in 10 would describe blog content as accurate (37%)

- 52% say they trust blog content somewhat (49%) or very much (3%)

Ipsos Reed used the following definition in the poll for a blog:

..web pages with minimal to no internal editing, providing online commentary that are periodically updated and presented in reverse chronological order, with hyperlinks to online sources. Respondents were further told that blogs could function as personal diaries, technical advice columns, sports chat, celebrity gossip political commentary or all of the above.

Who reads blogs in Canada? Here we follow the trends of the US quite closely.

men (48%) aged 18-34 (50%) with a post secondary education (45%)
household incomes of 66 thousand or more (44%)

The poll was conducted between June 2-12th via a representative sample of 3,378 online adult Canadians. (pdf)

via Neale News

With 60+ million blogs online I don’t believe this is a mainstream snapshot.
Depending on blog platforms, I think teens and college/university students are the largest number of blog users.
MIT
Perseus
Pew Internet & American Life Project
Sifry’s 2005 State of the Blogosphere

As far as I know, this is the first time a major polling company has looked at the blog readership in Canada.