Eh, the REAL 1234567890 day was Friday, February 13th 2009, 23:31:30 (GMT), which is 1234567890 in Unix time. The nice thing about that milestone is that it was compatible with all date formats.
The one mentioned in this article only works in Europe and other regions that use DD/MM/YY. The international format is YYYY-MM-DD, which would make it 2009-08-07, and the US format is DD/MM/YY, which would be 08/07/09.