I love a game of WOTR but I have been so bored with the missions in the GW rulebook, that I have even been moved to design, layout, and test my own mission for the game - just to add variety.
So I am really pleased that there is a new WOTR scenario on the GW website!
In terms of balance, we'll have to see. The victory condition is awesome. Good (or the defender) wins if they roll 2d6 at the start of any turn, and get less than the total number of Evil (or attacker) formations destroyed so far. The attacker gets unlimited reinforcements and wins by killing all the defenders. Only basic infantry (though the scenario suggest that this could be any one formation type eg Cavalry) return via the reinforcements. Any named heroes die permanently. The potential exists for Good (defender) to win on any turn, once they have destroyed three evil formations. This seems a little too 'random' or easy for Good, but NATCON would be 1000pts, which might make things a lot harder for them.
I'd be very interested to see feedback (via comments or to my NATCON email), since I am definitely looking at using this for NZ NATCON 2011.