As we all know Page Title or Meta Title is the most important factor in better ranking in search result. Writing a descriptive and informative page title led to a top position in different search engines. Google recently updated blog that contain information about how they improved their robot to show a better page title in their search result. They give advise to write a descriptive, informative and unique page title.
In some cases when Google unable to find page title or find page title less informative or not related to search query, in that case Google fetch page title from within the page, from ODP (Open Directory Program) or from any other source where they find Title informative and related to user search query.
For example if you title is like:
Example Meta Title: SEOFuture Blog Spot – Home Page
This title is less informative and search engines will unable to find any relevant keywords from the page title. In this case they will show page title from the other resources specified above.
In some case webmaster uses same Page Title for all pages and it is hard to differentiate page that related to user search query. Google try to find most relevant page title that comply with user search keywords and substantially it improves the click through ratio and help user to find most relevant website they are looking for.