This makes sense strategically. I've always said that text input is the missing link on the iPad. Apple never figured that out. On the other hand, I'm not sure that Nokia or Microsoft have either.
The original Mac had the mouse, which changed the game. The iPod had the scrollwheel, which made it tenable to navigate thousands of songs. The iPhone had the touch screen, and wasn't expected to be used for a lot of text-input so an on-screen keyboard sufficed (although I think Android may have surpassed Apple with this in the ability to switch out keyboards).
If the iPad is meant to be a laptop replacement, it fails with regard to text-input. There was no big gain in input like each of Apple's previous devices had (mouse, scrollwheel, touch screen).
If I were Apple, this is something I would focus on. There might be a solution. Not that I know what it is. But Apple has a lot of resources to think about these things. Microsoft at least did something, with the keyboard case. If Apple sold a first-party equivalent, I think it would be quite popular.