Today at Building Windows 8 blog, Steven Sinofsky has officially confirmed that Windows Media center will definitely be part of Windows 8.
Windows Media Center will not be part of the first pre-release builds. Some other features/capabilities will not be in the first pre-release builds including: Windows 7 games, DVD Creator, upgrade setup, Dot Net 3.5 (Note there are perhaps a couple of other relatively low profile items but just wanted to hit the major ones here). These are engineering decisions as well as business decisions.
Here what he says:
In addition a lot of folks said “everyone I know uses it.” As I said, we’re completely committed to delivering Media Center in Windows 8, but I wanted to share some of the usage data. This data in no way influenced not delivering it as part of the first pre-release build—we are as committed as ever to Media Center.
Our opt-in usage telemetry shows that in July, Windows Media Center was launched by 6% of Windows 7 users globally with the heaviest usage in Russia, Mexico, and Brazil (frequency and time). However, most people are just looking around; only one quarter (25% of 6%) of these people used it for more than 10 minutes per session (individual averages), and in 59% of Media Center sessions (by these 6% of users) we see almost no activity (less than a minute or two of usage). TV was the most common scenario we observed, and not surprisingly, traditional media (DVD and CD) are less common (and declining over time) than streaming and file-based content. By comparison, Media Player (66% of Windows users in July) and IE (88%) are popular rendering engines for all types of media content, including an increased volume of "premium" and streaming content. This is another place we’re reminded of the tremendous diversity of Windows activity.