With the current situation in Germany, Snowden would be dead or in a plane to Guantanamo in very little time. And I guess, even the German BND (comparable to the US NSA) would be helping. I would not trust any promises from a current German government -- by the way, how many US troops are in Germany? I guess, there is no count for US spies yet.
We have to remember, we are talking about our government, the same types that while fighting a war on drugs are also making deals with the Cartels that consolidates power under one and permits import of drugs into our country.
There was a person with a German passport years ago, he was wrongly held in Guantanamo for a while ... against all international rights. Even after they concluded, that there is no evidence against him, they still kept him for some years.
See here: http://en.wikipedia.org/wiki/Murat_Kurnaz
Do you think, only because Snowden has got some German looking waste-paper, the NSA will stop hunting him down?
Dream on!
But most people understand by asylum, that he comes to Germany.
I hope, you don't want to unembarrass Putin ;)