Sticky topics are the ones that remain at the top of the forum thread list no matter how recent the last post. Usually, interesting and popular threads are stickied to make them easy to find. So if your thread gets stickied it's because you're a really cool person.
Currently, the "Same sex marriages banned in 11 states" and "Wisconsin City Allows Teaching Creationism" threads are stickied, as shown by the thumbtack image to the left of their names. As long as they stay that way, they'll remain at the top of the page no matter what.
