An early image of the Blu-Ray box art for the upcoming Justice League: Crisis on Two Earths revealed a tiny little picture of the Spectre's head leading fans to speculate that he would be the focus of the first in DC's line of animated shorts which will be packaged with upcoming direct to video movies.
The guy has been around since 1940, but really has never gotten his chance to shine (in other words there was never any demand for an action figure, UNTIL NOW - act fast kids)
Basically, the guy is a supernatural spirit of vengeance type. He was merged with Hal Jordan for a time in the comics until Hal redonned his Lantern garb. To be honest, I am counting on the short to fill me in as well. In any case, it looks like 2010 may be a good year for old Spectre as he is also slated to appear in the team-up Batman: The Brave and the Bold series. After years of obscurity, it looks like the Spectre's stock is about to go way up.