Series 2006?

So I've got a couple of the "new" $5 bills that went into circulation
earlier in March '08.

I was a little confusled at first, because the bill is marked "Series
2006".

So I went to a few web sites, some at Wikipedia, some at the Bureau of
Engraving and Printing, and a couple of others, and they all say
that a new "Series" number is issued when there is a "major change" to
the bill.  Typically, the "major change" that requires a new Series
number is when one of the two signatures changes, but in general, when
there's a new bill, there's a new "Series" number.

The best guess I have is that (according to Wikipedia) the $5 bill
makeover was announced in June 2006, thus the bill is Series 2006.

So does anybody know why the new $5 bill is Series 2006 and not Series
2008?

--hymie!    http://lactose.homelinux.net/~hymie
  
hymie@[EMAIL PROTECTED]
 Without caffeine for 510 days
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