In a Sparkast in July 343 said they have been developing Halo 4 since 3-3.5 years so since sometime from January to July 2009. ODST was [url=http://www.destructoid.com/halo-3-odst-has-been-finished-since-may-148646.phtml]already finished in May 2009[/url] and as many of you know it contains a [url=http://misriahsolutions.files.wordpress.com/2011/06/destiny_awaits.jpg]hint[/url] at Destiny and the spherical alien ship (aka "the Traveller"). That means Bungie had propably thought of the Traveller before 343 came up with the Didact's Cryptum. BAM!