The idea of a mobile extension makes sense because .com websites are now becoming more complex since most people have high-speed Internet access. I don't like to visit .coms on my mobile, even though I have the capability, because the pages are slow to load, look different, and I am not able to type text as easily. However, I would visit pages that provided information and entertainment in a simple, easily-displayable format...
That said, ".mobi" takes me 9 key presses and one pause to type on my phone. In contrast, another mobile extension option that was available, ".wap", only takes 4 key presses and no pauses. I am sure that the .mobi administrators and backers would have considered this when they chose .mobi. This leads me to believe that they just didn't care, or had a plan to overcome the difficulty in typing .mobi names...
Hence the speculation of making the ".mobi" unnecessary to type, and turning the .mobi into THE mobi keyword system. Can you imagine how many billions of dollars the long list of reserved .mobis would sell for if they were essentially the keywords on all mobile phones to access the Internet?
I am sure that the .mobi admins would love it to happen, however the whole situation is a catch 22. The mobile phone software developers probably won't let users stop typing the .mobi until the extension is a widely developed and publicly accepted as THE extension for mobile Internet sites. However that will not happen until the public doesn't need to type the ".mobi" anymore...