OS X :: Recurring Date Seems To Be Everywhere In Mac 10.5?

I'm having a hard-to-explain problem. It seems that the date 05/01/2008 is everywhere. I bought my IMac in June of 2008 and I don't recall having this problem before. I'm a British user, so my iMac should be set at DD/MM/YYYY. I don't know whether this refers to a day in January or May. I wouldn't know where to search on the internet to see if a certain application or malware causes this glitch, but I thought someone on the forums might know.

A few recurrences of 05/01/2008 include:

All of the podcasts in my iTunes including Apple Keynotes, Quick Tips, Will it Blend and MacFormat have a release date of 05/01/2008
In System Profiler, below the titlebar, there is [my name]'s iMac and to the right the date 05/01/2008 18:26. Does anyone know what this date is a reference to? Could this be the day it was made?

I tried searching for files made on that day, but Find, didn't let me enter in a date in the field! Just for the record, I'm running 10.5.6 on a 2.4ghz iMac - the one released before the latest refresh.