I had to use www.com at school because my school's ICT administrator thought he'd be clever and block Google. He then blocked Mamma, Dogpile, Ask, Yahoo and Lycos...cunt.
I use google mostly, however there are times when I go on an image search hunt and Google doesn't always do the job. When that occurs, I tend that use other search engines for images and sometimes get some extra pictures or videos from using them.