"So we got our map for this region... what about the others?"
The map's been charted. Nathan Drake's next adventure begins in September. SCEE's official product page for Uncharted 2: Among Thieves has been updated, and in it, the release window is revealed to be September 2009.
We've yet to hear from Naughty Dog if this same release window will apply for North America, where it's still scheduled with a generic "fall 2009" status.