@Mop it up - I think there is a greater difference between DS and 3DS than Wii and WiiU, mostly because of the number 3 (even without seeing the red 3 logo). Numbers psychologically trigger a sense of sequentiality. 3 comes after nothing so it's looks and sounds like something different and new.
Back in December 1999, I was shopping at Best Buy and a confused mother asked me what the difference between Gameboy Pocket and Gameboy Color. This is one of those memories that I'll never forget. Despite the obvious colored logo, people still got confused. Even DSLite and DSi confused the F out of people.
At the same time, when I worked at the video store, I had to refund/exchange rentals for parents who rented a PS3 game for their child's PS2. It didn't happen terribly often but it happened. Still, I feel like Wii 2 would have worked better than WiiU and even WiiHD. However, rebranding the console may have been an even better choice. Not that it matters now, but the more I think about it, the more I'm siding with rebranding, even with a different silly name.
@MaryJane - I'm confused. Wii peripherals ARE backwards compatible. Are you referring to the tablet controller being forwards compatible with the original Wii? If so, I think that would be a terrible idea and confusing for everyone everywhere.
Also, word of mouth isn't going to change or fix stupidity. Nintendo marketed and branded the Wii specifically to the lowest common denominator. It promoted ease of use because buttons were deemed "complicated." They named it "Wii" because it's easy to say and remember in any language. WiiU practically does the opposite.
To echo what I (and GP) said in a previous post, I think it can go either way. Rebranding and requiring new peripherals avoids confusion but obviously would be very pricey. Keeping the brand and being backwards compatible may ease people into new hardware and is far less expensive, but it may severely confuse people. I wonder how many of those same people would end up rebuying the old peripherals because they thought they HAD to. It's a thin line, fo' sho'.
It's kind of like buying a car. When you buy a new car, you don't strip the tires and seats of your old car and pay less for the new one since you totally can just install the old seats and tires. You have to buy all new stuff and it's expected and people go in knowing that's an expectation. At the same time, I wonder how many people would want to do just that if they could save like $1000 on the new car and if it would make them far more likely to buy the car if they could. Hypothetical situations are hypothetical.