http://www.reuters.com/article/topNe...rpc=22&sp=true
Obama admits he spoke incorrectly. I personally believe that he used the "term" uncle correctly. I know it was it great uncle, but I also do not use the term "great" wen referring to my great uncles and aunts.
That being said I also believe he used Auschwitz instead of Buchenwald for political reasons. I believe he used Auschwitz because that is more well known to the general public. I could be wrong and this is just my opinion.
On a side note I have been to Buchenwald and the Germans have done a great job in keeping it mostly intact and teaching what really happened there so it does not get repeated. My great uncle also helped liberate Buchenwald.