An interesting article is up on FoxNews arguing that the Times Square Plot may have been a dry run rather than a full-scale attack. I'm not sure where I stand on this, but I'd suggest taking a look:
Cross-posted at World Threats.
It appears it took Shahzad two days to figure out an escape plan – fly Emirates Air to Dubai, the major airline hub in the Middle East, and change planes for Pakistan. He made the reservation on the way to the airport, paid cash, used his own passport, and had no luggage. If he was supposed to survive the blast, he would have preplanned an escape route, complete with fake passport, and scrupulous avoidance of the one place they knew we'd look – international flights to the Middle East.
Why a dry run? To flush us out, to determine what surveillance we had in place – cameras, license plate readers, undercover cops. To see how difficult it would be for a van filled with explosives to get to Times Square and stay there long enough to detonate. To see what our response was – how would law enforcement react and the public would react. To see how easy it was for an American citizen to evade detection beforehand.