This is from the databank at starwars.com. This confirms that 1. Kenobi WILL battle Anakin (of course) and 2. It was the duel that "created Vader" (caused anakin to live in the suit)!!
Here is part of the write-up:
Fueled by rage and discontent with the pace of Obi-Wan's training, Anakin challenged his master to a duel. Despite newfound power bestowed by the dark side of the Force, which added to his already formidable abilities, Anakin was grievously wounded in the fight. His burning anger kept him alive, and he was forever scarred not only by his wounds but also by betrayal.
So for those that theorized a long time ago that Palpatine would cause Anakin to have to live in the suit(from sith lightning or lightsaber duel), it appears that idea was incorrect. I remember one point in your arguement was: (ROTJ) Yoda said, "Luke, do not under estimate the power of the Emperor, or suffer your father's fate you will."
Just wanted to share!