People still dont get how pricing works when you have existing product.
Cost to produce the existing Elite with 120GB HDD > Elite with 250GB HDD.
Cost to produce the existing Elite with 120GB HDD much > then new Slim with 250GB HDD and WiFi
Cost to produce the existing Arcade much > then a new Slim Arcade without HDD
So if you dont release the new Slim with HDD now you continue to produce a more expensive to produce console. Not smart.
If you release new Slim with 250GB HDD at fall price of say $249 then the current Elites need to go on sale to $199. Arcades to $99.99. So you release Slim at current price and reduce the other older SKUs by $50
Later this summer when stock is cleared you introduce the Slim Arcade and Skim with Kinect SKUs and lower the price fo the Slim 250GB.