This story is going on and on and on ... and nobody knows anything.

AMD stated last year at a telephone conference that BD wont be AM3 compatible.
Now MSI launched the GD65 a few weeks back, which comes with a mysterious AM3+ printing.
Explanation from MSI: There will be AM3+ (yes, AM3+) CPUs that will fit in the board socket (which has an AM3 socket).
However we know that the AM3b socket has 1 pinhole more. That means, a AM3b CPU that will use that pin, wont mechanically fit into AM3.

The solution now is that AMD will do the same as with Deneb: First launch BD in the old socket AM3, as back then with Phenom2 920&940, and a bit later the real deal with AM3+.

In any case, the (desktop) marketing would have been abysmal bad, lots of people didn't buy AM3 last year, because AM3 was suppose to be a dead end like 1156, thus you buy the product with the better performance, i.e. Intel.