Science and Technology: Space Shuttle Launch Delayed by Technical Problems http://ping.fm/eQe5O

Africa: Libyan Forces Clash with Tunisian Soldiers http://ping.fm/6dVpU

Prince William Marries Catherine Middleton http://ping.fm/jxh75

Middle East: Protest Crackdowns Leave Almost 62 Dead in Syria http://ping.fm/iORHm

USA: Obama Consoles Survivors of US Storms http://ping.fm/0i89a

Roads to close in Istanbul for May Day http://ping.fm/0vyqe

Sprawling devastation as US storm toll tops 300 http://ping.fm/dy8Xm