Here is the full announcement from Sega West:
SONIC THE HEDGEHOG PC DIGITAL DOWNLOAD EXTRAVAGANZA!
LONDON & SAN FRANCISCO — 19th January, 2011 — SEGA® Europe Ltd. and SEGA® of America, Inc. are delighted to announce three exciting Sonic the Hedgehog adventures will be available for the PC Digital Download market from today.
Following on from the successful launch of Sonic Generations™ for the PC digital market in December 2011, the stunning new downloadable Sonic Generations™ Casino Night Pinball Stage is now available, adding to a grand adventure with Classic and Modern Sonic racing to defeat the Time Eater, save their friends and find out who really is behind all these strange happenings.
Sonic CD™ follows the classic story line from the original 1993 MEGA CD™ system game with Sonic racing through time to save Amy-Rose from his evil mechanical twin Metal Sonic. This super speedy remake includes brand new features and will be hitting PC digital stores for the first time today!
Finally, as an added bonus the much anticipated Sonic the Hedgehog™ 4 Episode I will be available, enabling PC owners to enjoy the beautifully rendered HD environments of the much-loved special stages and a variety of different Zones, all inspired by the Mega Drive era. The Sonic 4 saga will continue to grow in 2012 with the new side-scrolling adventure Sonic the Hedgehog™ 4 Episode II releasing later this year for PC digital download.
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