Until 16.00 there were 30.09% of Latvian voters or 445 076 persons who voted in the referendum already. The next announcement from the Central election bureau should be at 20.00 local time.
Updated (Monday morning)
At the end 628 831 voters turned out and it was insufficient number for considering this plebiscite valid. However, this number means that 40,09% of all the eligible voters in Latvia wanted to see transformaion of the stagnant political system. Among the referendum participants there were 608 000 voters who said AYE and 19 000 naysayers.
To give you comparative perspective there were 469 934 voters who voted for the governing coalition parties (People's Party (TP) 177 481, Union of Greens and Farmers (ZZS) 151 595, Latvian First Party and Latvian Way Union (LPP/LC) 77 869, Fatherland Union (TB/LNNK) 62 989) during the last parliamentary elections in 2006, which could have been announced illegal by the Supreme Court of Latvia, and when the total voters turnout was 60,98%.
One issue is clear now - the rift between the governing "elite" and the voters cannot be really healed without snap elections in Latvia.