Sunshine: SM64 with a squirt gun
Galaxy: SM64...IN SPACE!
Sunshine: Stopped playing after 70 stars (oops, "Shines") or so.
Galaxy: 69 stars, not going to stop anytime soon.
The first time I ran "off" of a planet, only to wind up on the underside I knew this was better than Sunshine. Putting the game in Space gave Nintendo much more game design issues to use. On the other hand, Sunshine didn't have anywhere to really innovate the SM64 formula.
SM64 improvements
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Sunshine:
You can squirt graffiti/mud/goo
You can hover
You can Superjump
Galaxy:
You can run under platforms
You can make sloppy jumps and the platform's relative gravity will save you (extremely IMPORTANT for 3D platformers without double jumps)
You can grab stuff by just pointing at it
You can have localized gravity (Bowser stages get lulzy with this)
Galaxy's new ideas are MUCH more innovative for platformers than Sunshine's. With these ideas, Nintendo could design much more diverse and varied levels than they could with Sunshine.
It wins right there.
Then Galaxy adds 2P support to let parents, casuals, and "I only watch gamers" types join in the fun.
There is no such thing as a console war. This is the first step to game design.
