It is by no means homosexual, and does not involve sexual feelings.
This 'man crush' can be based upon admiration and sometimes jealousy.
Men can often deny this man crush and slander their man-crush's image and achievements since they are jealous.
However, they feel very strongly about this crush, and it can often be based on the female attention this male receives.
"Mate, you've got a man crush"
"Yeah, we played twister and scrabble and watched movies, and spent all night talking, bizzatch."
"Dude, you're 35, acting like you're 12, and you're using his language. You've got a man crush."
A 'man crush' can basically be described as not a homosexual lust, but a human lust.