There are a lot of questions to answer regarding Avid's upgrade policy to Media composer now that Xpress 'Pro is DOA. I've been answering the same questions a lot (Sometimes in the same post) so I wanted to clarify a few things in one post. Special thanks to Michael Butcher for helping me to assemble this:

Upgrade price from any version of a commercial license of Xpress Pro to Media Composer with 3rd party software bundle: $495 (US)

Upgrade Academic Xpress Pro (any version) to a Commercial version of Media Composer (Including 3rd party Add-ons) is not an upgradable product at this time. Please contact your reseller for a price.

Upgrade pricing is available for Xpress 'Pro academic to Media Composer Academic. Again, contact your reseller.

Purchase Media Composer Academic: $295 (US) (Anyone holding a valid State Educational Institution ID)

Purchase Media Composer Software: $2495 (US)

European prices are 500 Euros and 310 GBP Available now in the Avid store.

Xpress Pro will continue to be sold through Q2 of 2008.

Avid will support Xpress Pro through March 13, 2013, but the program will not be updated beyond the current version (5.8).

Regular Mojo and Mojo-SDI will work with Media Composer.

If you're running an Avid certified machine with the newest version of Xpress Pro, your computer will most likely run Media Composer sofware. Check the Media Composer specs to see where you system might be lacking. Media Composer System Requirements

Purchasing Assurance Contracts: Changes (if any) are not determined at this point, to be announced at a later date if changes will be made.

When will the Xpress Pro to Media Composer upgrade price expire? This is currently considered a set price for the upgrade from Xpress Pro to Media Composer with no expiration date set.

I need 720p/25 support, which is slated for a future release. Will it be added to Xpress Pro? No. Xpress Pro will not be further updated. You will need to update to the Media Composer version when 720p/25 is supported.

Will Xpress Pro run on Leopard or Vista? Not in a supported configuration. Again, Xpress Pro will no longer be developed, so Leopard and Vista will not be supported for Xpress Pro. Upgrade to Media Composer when the software supports these operating systems.

Is there any price cut on hardware? There have been no hardware announcements to date.

Can I update Xpress DV to Media Composer? Yes, but not all in one install. First, buy the upgrade to Xpress Pro for $495 and update your dongle. Then buy the Xpress Pro to Media Composer upgrade for $495 and update your dongle for Media Composer.

Do I get third party programs with the upgrade? Yes. Upgrading a commercial license of Xpress Pro to Media Composer will include the third party software bundle, including Boris CC effects. Currently, BCC is not a part of the software download purchase from the Avid store. Avid online is currently working to get those plugs bundled with the download but no word on how long that will take.

For more info, here is Avid's product page announcement

At the Bottom, you will find an even more detailed FAQ

Additionally, ifyou want to see what you will be adding with the upgrade to MC,

This article should shed some light.