First coined by "Wobbly Bob", and popularised by Pete Bennett on Big Brother 2006. Mr. Bob claims to not have a firm definition of the word; these phrases come to him and catch on.
Whatever Mr. Bob's intentions and hopes, if indeed he has any, the word has become a meme in popular culture which can be used to express delight, admiration, excitement and a number of other positive feelings.
"Nikki man, eezamanah!" (Pete expressing his feelings for an absent hosuemate to a friend in the big brother house)
"Wobbly Bob! EEZAMANAH!" (Pete spotting his friend in the crowd on Big Brother interview)