And a damn good job he did, as much as I love the series, the middle of it was a grind to get through. Seemed like a lot of dress twitching and braid pulling to me. Especially book 10, although the end was awesome getting there was painful (and I took a day off work to read it). But Sanderson brought the series back to vivid spectacular life again.
The middle books grind down because Jordan kept wandering into side plots that would have been better served as standalone books (say, similar to how the Dragonlance books were handled). He knew where the finish line was, just wasn't in a hurry to get there.
Sanderson, on the other hand, was brought in to do the "last" book. (Yes, Jordan had claimed there was only *one* book left). It's pretty easy to see Sanderson picking out the leftover plots, punting them to the curb, and goosing the accelerator to get the plot train home ASAP. Which also made the books way better, since we finally get to the finale.
I think it could make a good mini-series, though - you can consolidate a bunch of points, ditch some of the sideplots that aren't necessary, and keep the plot train moving.