"PageRank relies on the uniquely democratic nature of the web by using its vast link structure as an indicator of an individual page's value. In essence, Google interprets a link from page A to page B as a vote, by page A, for page B. But, Google looks at more than the sheer volume of votes, or links a page receives; it also analyzes the page that casts the vote. Votes cast by pages that are themselves "important" weigh more heavily and help to make other pages "important"."
So as you can see, increasing your pagerank is vital for your blog success. If you can make your website important in the eyes of google search engine you're saved! The main question is how...?
First of all, Google use spiders that visit your URL regularly.. So you'd better have something new for the spider or else you will be badly indexed. You have to show google that your site is worthy to be visited.. and that's by building a huge and updated content about the subject you deal..
Second, you have to make websites linking to you ? If people are linking to you that means your website is important.. But don't wait for them until they link for you ! Do it by yourself! submit your website or blog in directories and blog search engines. If you're a blogger submit your articles in E-magazines with putting your URL as the source of the article.
Third, visit other websites and ask the webmaster for partnerships. Exchanging links will help improving your PageRank and will increase the number of your visitors too..
Finaly, never copy and paste other's content. Any copyright violation could index your URL in the black list !!
You can check your pagerank using the google bar or visiting this website.