The new Linksys E4200v2 N900 router has been confirmed to be using a MARVELL 88W8063 a/b/g/n chipset instead of a Broadcom chipset used in the orignal Linksys E4200v1 N750.
This may have some impact if one was looking to use an alternative firmware at a later date on this router.
DD-WRT or Tomato firmware only runs on a Broadcom chipset.