Already been posted. ABP for short.

One point is really interesting.
IF they do release a Blu-ray add-on, it will void the argument that PS3 is the only console with Blu-ray. I mean, a big selling point for the PS3 is the Blu-ray. If it is provided to 360, then there's really no argument there :S
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Thanks!

i dont think this will happen,though maybe the next xbox will have it

I can see this happening. As an add-on the consumer will be covering the license fee to the blueray group (not just Sony..) The fee will be built into the price. Microsoft will not be paying Sony silly guys.

It would take away a big reason to purchase a ps3 over the 360 as.. you would be able to play bluerays. If the price is reasonable I would actually buy one as it seems the format war is over and I as of yet do not plan on getting a ps3.