Just found at Dienekes what seems to be the definitive evidence for a south to north colonization of East Asia. This was quite obvious to me but will be hard to swallow for those who are used to other classical (but seemingly erroneous) interpretation.
The press release emphasizes this fact:
The scientists also reported a clear increase in genetic diversity from northern to southern latitudes. Their findings also suggest that there was one major inflow of human migration into Asia arising from Southeast Asia, rather than multiple inflows from both southern and northern routes as previously proposed. This indicates that Southeast Asia was the major geographic source of East Asian and North Asian populations.
The HUGO Pan-Asian SNP Consortium, Mapping Human Genetic Diversity in Asia. Science, 2009. (Paywall but supplementary material is free).
From the supplemental material I picked this max. likelihood tree, where the Eastern Eurasian divergence node seems quite apparent:
Notice that the Papuan sample is negligible: only 5 individuals!
Also discussed at BBC.