Kapow Toys have posted over on TFW2005 that the upcoming Transformers Animated 2-packs of Optimus Prime and Blackarachnia and Megatron and Prowl, will both be Walmart exclusives in the US.  Both Prime and Megatron will still be the battle damaged versions.  Also they report that Shockwave and Skywarp are set to ship at the end of October / start of November within the US.

Here is the text from the back of the box of the two double packs.

The Revenge of Blackarachnia

Long ago Optimus Prime was forced to abandon Blackarachnia in the caverns beneath the surface of an alien world. There she found herself surrounded by a terrifying horde of bizarre spiders and she was forced to reformat herself based on the strange organism to survive. The experience twisted her and drove her away from the autobots and left her with an undying desire for revenge on the former ally who left her to her fate. She has come to earth in search of Optimus Prime and she will not stop until she has destroyed him and everything he holds dear.

Battle In Space

In Space over a strange alien world Megatron carves his way through the hull of the autobot spaceship with his fusion cannon. Inside Prowl and his fellow autobots wait, knowing there is very little chance of defeating the Decepticon leader in a fight. Prowl knows his only chance is through stealth and skill. When it comes time to meet the mighty Megatron in combat he relies on his holographic projectors and speed to avoid being hit whilst tagging his opponent with every combat technique he knows. Unfortunately even his most powerful attacks bounce off the invincible armour of the Decepticon tyrant.