Gateway Pundit has the letters and the scoop. Go check it out - apparently, Al Sharpton read Obama's original letter at the funeral for Heavy D. 

Over at IBD, an editorial that focuses on the issue:

...'I don't take these folks too seriously," President Obama recently told the Virginian-Pilot, referring to a group of former SEALs who formed the Special Operations OPSEC Education Fund Inc., to run ads attacking the leaking of details of the Osama bin Laden raid and other national secrets to further his reelection chances.

Apparently the president doesn't take the sacrifice of Navy SEALs who've fallen in battle and the grief of their surviving families too seriously, judging from the form letter sent out to the families of 17 who were among 30 U.S. service members killed when a CH-47 Chinook helicopter transporting them crashed in Wardak province, Afghanistan, on Aug. 6, 2011...

 

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That's not an electronic pen - those signatures are different. As for form letters, I don't know what the practice is in the US.

 

Also, I'm reminded of the whole 'controversy' after Gordon Brown, a man with only one functioning eye and awful handwriting by his own admission, apparently mis-spelt a woman's name on a letter.