Nice find, kotaku always has the best rumours :D
If nintendo wanted to include these things in the first place, they would have included a DVD player with the wii. Fortunately, that's possible with softmodding.
As for the wii u, well, nothing is unhackable :) - so I guess we can at least make it a DVD player.
Why are nintendo consoles so cheap? This is the answer. They don't include much stuff in their consoles because they don't need to compete with other consoles. Nintendo consoles are meant to be different.
But hey, the blu-ray player would still be nice ;)