Coin World reports that an unknown number of the 2008-W Burnished Silver Eagles have been struck using the reverse die type of 2007. Coin World was first notified about the variety by John Nanney of Leesburg, GA.
The reverse type is most easily distinguished by the appearance of the “U” of “United States.” Coins with the reverse of 2007 will have a bowl shaped “U.” Coins with the reverse of 2008 will have a “U” with a spur on the right side of the letter. Other noticeable differences include the configuration of the stars and the tilde and spacing between the worlds “Silver” and “One.”
NGC has confirmed that they will be specially designating coins with reverse style of 2007 as “Reverse of 2007.” Check out their recent article for diagnostic images and details.
There has been no official word from PCGS about whether they will be designating the coins.
Although the relative rarity of the coins with the 2007 reverse style is still unknown, prices have quickly escalated. The coins were initially available for as little as $69 each on some websites. Those quickly sold out. Now eBay auctions have coins bid up to as much as $685 for examples graded NGC MS 70. Here is a list of current eBay auctions.
2008-W Silver Eagles Reverse of 2007