I was looking at it yesterday. I did have to play around with it a bit to get it to work, though.
On the main
DVC site, under Destinations and Worldwide Stays click Hotel Exchange.
Scroll down to Hotel Exchange and click on Book with Interval Online - do not click on "Search Now" in the text below. That just gave me the spinning circle of death.
Once you're in II, click on Hotel Exchange (under Welcome Disney Vacation Club Member), then Search Hotel Exchange
It will then take you to a screen asking you which unit you want to exchange. Ignore that and click on the blue box on the right that says Hotel Exchange.
That should take you to the search engine. There appear to be lots of options for larger cities and you can choose between using points, cash or a combination. I didn't look that long, so I can't speak to the value. But as it's just regular hotel rooms rather than villas, I'm not sure how good a deal this is. I'd definitely have to compare cash prices or using our Marriott rewards points over this before booking anything. Still, it's nice to have the option!