Can SuperObama save Africa?

Obama's recent visit to Ghana added fresh woods to the bonfire of the discussion about "western" policies for Africa.

Obama is a superhero in most African countries. In Gambia the truck and bus drivers usually have three stickers in the front window: Bob Marley, Madonna and Obama. For many he is the new hope, so what he says and does toward Africa matters.

First, why did he decides to go to Ghana and not to another country?
some thoughts here and here

What did he say?


Reactions to the speech?
"Bill" The Watchdog couldn't be outside the discussion. He grades the speech, and gives one of the worse scores to the idea of support an African Green Revolution. But other people seems to be more optimistic about this.
UPDATE: The grades from a second reader.

Will Obama's superpowers be the definitive answer to failures of Western policies?