Card is nothing, if not a controversial figure in science fiction largely because of his outspoke, and many would argue inconsistent political views. There's quite a lot about this in his Wikipedia entry, and really there would be no way to avoid discussing it due to his tendency to use his best-selling name recognition as a soap box for his personal dogma. A devout Mormon, characterized by many as homophobic, he identifies himself as a Democrat while clearly being as pro-military (and arguably pro-police state) as the farthest right of hawks, and manages somehow to disagree wholeheartedly with both Darwinism and Creationists. In fact, it's rather hard at times to figure out how he has risen to such popularity given his ability to piss off just about everybody at some time or another.
Of course, that popularity stems from his ability to write fiction more than anything else. Card is easily best known for his 1985 militaristic SF novel Ender's Game which has continued until this day as a series and will soon be made into a motion picture. He won both the Hugo and Nebula awards for this novel, and in fact won them again for the sequel Speaker for the Dead, making him the only author thus far in history to win both awards two consecutive years in a row.
His own official web-site is here and features a preview of his upcoming near-future novel Empire which seems likely to stir up all new political controversy as it proposes a future shooting war between left and right wing Americans.
Here's an interview from 1999 to round things out.

