Sony turning what was originally planned to a simple CD drive add-on for the SNES into a full-blown console was pretty bold.

DMC to DmC ... the whole process seemed like that to me, especially in the initial stage.

Microsoft bundling the Kinect with every XB1 is pretty bold if you ask me.

Agreed. I can't even unsee it anymore. I heard the ending was provacative but fuck I didn't want to know it—that ruins some of the surprise and effect of the scene.

All the companies who released singleplayer games which only work if you are connected online.

NES control.
who would imagine to play a game with a controler in that format?
keep N64 cartridges.
PS3 price, wii controler, and DS double screen scheme.

wii U was not bold at all.
they bet in what had worked in DS, and kept the wii compatibility with controlers.

In gaming: SSB i think was bold.

You can be stupid and bold. It's not the good kind of bold, but it is bold nonetheless.

Replacing DVD would have the same problems as 3D TVs I reckon; after upgrading to DVD/HDTV people don't want to replace again so soon.

Technological advancement outpaces people's willingness to adopt it.

I'd have to say the PS3. It featured many expensive technologies to future-proof it, it was difficult to program for and it was for people who had 2 jobs, like a certain spokesperson mentioned. Things looked pretty bleak at the beginning, but right now it's the second best selling seventh generation console with a vast library and with good support still near the end of its life. It's probably the boldest for me because it's still doing good after the problems in the past.

Convenience has more to do with it. From VHS to DVD huge improvement in usage and storage. VHS was dropped like a brick when hdd pvr took over the recording side. Same with HDTV. Big screen tvs were already available long before, dvd quality video too with Laserdisc (since 1978) and MUSE Hi-Vision LD (since 1994) Yet the discs were big and heavy, big screens tvs even bigger and heavier, inconvenient.
Light weight flat screen TV drove the adoption. For many years people gladly put up with ugly stretched or cut off 4:3 picture on their nice flat 16:9 screen.
Blu-ray, big step up in quality, no extra convenience. Actually it's more hassle than dvd with less user control.
3D, glasses required, big inconvenience. Ever brought any realD glasses home from the cinema? How do they look after a week with kids...

Blu-ray, 3D blu-ray, 4k blu-ray, all destined to become a high end option like Laserdisc was. Streaming is going to replace DVD.