While the cancellations of Mega Man Legends 3 and Mega Man Universe sting, they're not the first Mega Man projects to come to an unceremonious end at the hands of Capcom management. GameSetWatch has a brief retrospective of the other Mega Man titles that fell by the wayside over the years spanning the 3DO version of Mega Man X3 up through the Game Boy Advance compilation of Mega Man Game Boy titles, Mega Man Mania.
Originally released for the Super NES, Mega Man X3 saw the addition of animated cutscenes and remixed music in the transition from cartridge to CD-ROM. While the PlayStation and Sega Saturn versions were later released in Japan and Europe, the 3DO edition was never released anywhere in the world. Mega Man cancellations continued for years afterward.
Some of these hurt more than others. Mega Man on 3DO isn't really mourned since we did eventually get the comparative version for the Sony PlayStation and PC. The article covers the upgraded version of the Mega Man X Collection that was slated to contain all kinds of enhancements and extras that were removed before release in order to use in the Maverick Hunter X PlayStation Portable sequels that never happened, and those are dearly missed. Mega Man Mania may hurt most of all considering how much of a bargain it would have been. Five classic-style Mega Man games on a single Game Boy Advance cartridge? Sold! Or, rather, it would have been had it been released. I stopped by the Capcom booth back at E3 2005 and asked about the fate of the vanished game, and the folks running the area had no idea to what I was referring. Mania was a lost cause long before it was officially cancelled.