It's the same as with anything else. They have sources who are actual studio employees who have told them things off the record. As we've seen many, many times, these developers might only know part of the puzzle, or the hints they're dropping are vague enough that the writer(s) didn't understand it clearly. The sources might be talking about material that has purposefully been obscured and they don't realize it. There are tons of possibilities as to why that article might not be accurate when the final product is released. Everyone should be aware of that.
"A handheld device wouldn't explain why western 3rd party developper like Ubisoft,Take-Two,etc ... would be excited for the NX."
As for this, however, it could all be nice-nice PR-talk unless they announce games. Remember that Ubisoft mentioned the NX exactly once during a long (loong) presentation and that was for Just Dance.