I didn't think the DSi, XL, L etc. didn't count since Rey were simply expansions that optimized the original hardware on the DSPhat.
Besides, M$ has done it too with their Xbox line, so has $ony with their Playstation brand, and, if we count phones as gaming devices, so has Apple with their iPhone line.
And let's not forget how many IPs Nintendo's come up with. Pretty much most games Nintendo comes out with these days are all Mario, Kirby, Zelda, Metroid, and Pokemon games. It's rare to hear Nintendo making original stuff nowadays, and frankly, I don't blame them. Why fix something that's broken? As long as those franchises keep bringing in money for Nintendo, they're not going to be too trigger happy on the originality for a long while. Given that the Wii sold nearly twice as much more than the other companies combined this gen and the DS easily became the most popular handheld, I seriously can't blame them for continuing the Wii and DS line if it's going to give them more money due to brand recognition
Although to be fair, Nintendo has been more original with the console names than the others, with the N64 and GC and all though they probably didn't go with another N64 console because we don't even play in bits anymore and I'm guessing the GC since the Wii didn't look like neither a cube nor did Nintendo want the console to be associated with one of the least srs consoles of the gen