The Post has some more information on American Crossroads here.
In that, American Crossroads is aiming to take a page from what Democrats did in 2004 — constructing a shadow party to spend hundreds of millions on the presidential election. The Democratic effort — a three-headed beast that included the Media Fund, which handled ads, America Coming Together, which handled turnout, and America Votes, which coordinate between the two — was lauded for its broad reach but disbanded after the election in the wake of a series of campaign finance rulings.
Both parties have tried to recreate the fundraising successes of 2004 but have never come close. If American Crossroads can reach their lofty fundraising goals in 2010, it could be a major player in the 2012 presidential race.