The Sega CD's augmented tech far outpaced that of the Genesis—a critical factor, since the CD add-on was linked with the base console. A single bottleneck clogged the entire system.

Next-generation consoles will get a new 3D Sonic the Hedgehog game next year, after Sega teased the prospect on Thursday. The trailer for the as-yet-unnamed game sees the fearless blue hero ...