How many of you are using it as your default search engine? I am. I don't think it's as good as Google, but I think it's good enough, some things are useful, like the quick links, and at least the user interface is cleaner, there is no stupid auto-complete etc.
What really makes DuckDuckGo so great is the bang syntax. Searching for '!foo bar' will automatically redirect you to another search engine for your search (e.g. '!cpan mechanize'). Here are a few I use frequently: !google - Google !images - Google Images !cpan - Perl CPAN !perldoc - The Perldocs
Duck Duck Go makes it so easy to search everything.