Its true, check out this chart:
http://vgchartz.com/hwcomps.php?cons1=Wii®1=All&cons2=PS3®2=All&cons3=X360®3=All&start=39418&end=39481
From the numbers from this site the PS3 has won 10 straight weeks! Hasn't lost a week yet in 2008.
p.s. theres no need for wii fanboys to say wii has won 300 straight weeks! lol