Two key things from their post stand out:
Puerto Princesa
Back in September, Bungie.net user “Motarius1″ posted his discovery: Puerto Princesa in the Philippines is the real-world location of the “Destiny Map” Bungie has been using so frequently. The artwork is lifted directly from a U.S. Coast and Geodetic Survey nautical chart first published in 1904.
People who followed the Destiny bread crumbs will probably recognise this cartography as the basis for the 'Star Maps' Bungie have been using all over their website.
The second thing has been covered before: "Destiny Awaits" as found in Halo 3: ODST.
Given the leaked images of the giant space ship known as The Traveller are now out, looking back at the in game poster shows the hint was an even bigger tease than first thought - is the circle around the Earth actually The Traveller?
Destiny Awaits
The Traveller
Official Bungie images:
If the circle is indeed the Traveller, Bungie was playing a very long game in their planning for Destiny - Bungie split from Microsoft prior to the release of ODST after all...
No doubt there will be more hints and speculation to come!