Used by the adolescent population at large to describe something so bloody cheesy, that it actually becomes amazingly fantastic. The use of the word cheesetastic usually implies a derived pleasure from the utter cheese of a situation or phrase.
Be cautious, large danger of over usage.
*watches soap opera in which lead actress is pregnant with the baby of her brother's wife's father's uncle, and is married to her father*
"Dude, her unfortunate pregnancy situation is so totally cheesetastic!"