Quite a bit of misguided information here, IMO (and I've ridden the Divide twice).
The Divide has superb resources (maps, blogs, experienced riders) for planning things. Even on a daily basis, you can look ahead and figure out your resupply options. That makes a gigantic difference compared to some of the less well-known routes.
The Divide is mostly made up of very easy trails. The climbs are mostly moderate gradients and there is hardly any technical riding.
For me, two things make it interesting:
The broad expanses of North American country - big skies and mountains on an epic scale.
Racing it as fast as damn possible.
But people fret too much. I rode the Divide the first time in June 2010 and my training started in March 2010. I'd spent Jan + Feb in New Zealand getting hardly any exercise.
If you really intend to do it, set yourself an aggressive goal: Go next year. Otherwise it'll just be in the long grass forever.