What is Nintendo hiding?

Following Nintendo's less-than-thrilling announcement of text communications for Mario Kart Wii, the author asks if there might not be a more serious reason that the company has yet to integrate voice comms into any of its online titles.

From the article: "I can't help but wonder if there isn't a more insidious reason that we've yet to see meaningful voice chat from the Wii. What if the Wii CAN'T do it. What if it's such an underpowered system that they can't get it to work reliably? Remember when Sony left rumble out of their controllers, calling it "last-gen." Later we found out that the real reason was that they were getting their pants sued off for patent infringement.

I'm not buying what Nintendo is selling here (both figuratively and literally). I think they grossly underestimated the demand for voice comms when designing their mac-influenced PS2. But what the hell do I know? Why do you think Nintendo keeps screwing the proverbial pooch with their online experience?"