The Blu-ray release of The Ultimate Matrix Collection will replicate the full seven discs present in the HD DVD release.  There has been no announcement on a Blu-ray release of the Complete Matrix Trilogy.  The full supplement package of the HD DVD release are expected on the Blu-ray, although no official specifications have been released at this time.  Early details report that the Blu-ray collection will have about 35 hours of extras and In-Movie Experience picture-in-picture commentaries for all three films.

Additionally, there has been a confirmed upgrade.  The Animatrix will be present on the Blu-ray and upgraded to full 1080p, unlike the HD DVD counterpart.  Stay tuned for more details.