One things i like to know is why all the companies add the letter 'i' to their products to make it cool?

at least they added it to the end rather than the head.
Imagine. iDS. heh.

I think that many of the extensions that tried to use the GBA slot aren't "must have". Its an interesting direction for the DS.
Its kinda interesting tho, essentially, minus the camera and double touch screen, the DSi  feels like nintendo's way of trying to venturing into portable applications, the realm of homebrew.