Welcome back to "Doggerel," where I ramble on about words and phrases that are misused, abused, or just plain meaningless.
Whenever there's a "what is skepticism?" thread on the JREF forums, you can bet that there'll be a lot of debate, but I suspect that most of the people who use this bit of doggerel would be excluded from all the definitions, or at the very least, tucked away into a very weak sub-category.
To be simplistic about it, a skeptic is a person who wants to see evidence to back up a claim, especially "extraordinary" claims. For that reason, the claimant should be providing evidence, good arguments, etcetera. Unfortunately, this doggerel is often followed by appeals to other ways of knowing, anecdotes, and other spurious forms of (non-)logic.
A skeptic should know what it would take to convince him. By extension, ex-skeptics should know what it took to convince them. They should also know what wouldn't convince a skeptic. One example that comes to mind is dowsing and the Ouija board: They can be surprising, when they seem to move on their own, but you have to perform controlled tests to see if the answers they provide are accurate, and not the result of information leakage combined with an ideomotor effect. Not much point in positing a new entities when there's another known, probable explanation.
One thing I suspect contributes to the problem is the "Hollywood skeptic": Horror movies often have a contrarian straw man of a skeptic who doubts the existence of the monster right up until he's eaten by it. Fortunately for movie goers, reality is more often like the original Scooby Doo: It's always some guy in a mask. Unfortunately, however, it completely distorts what people think it means to really be a skeptic.