Yep I know the first 5 digits of your serial number
W8730
It's a standard apple uses your serial number starts with W8 because it came from the shanghai factory the same factory as mine. The next 3 numbers are probably 730 as that is the year (7) and week(30) that your imac was made. The rest will be different as the next three letters designate(in base 34) what sequential number yours was that week and then the rest is model number and such.
Oh and it may not say late 2006 because the 24" ones haven't been updated so there is no late, early, or anything.