I don't know if this was covered when we went over the new rule changes recently, but one thing I noticed over at the mothership is that fans around the league will be able to see what the referees look at when they go under the hood to review plays. Anything the ref sees, the fan inside the stadium will also see.
Here's the article from Jay Adams on the subject. One thing I had forgotten was that all turnovers will be replayed. Sounds great, in theory, but here's to hoping they don't actually review the cut-and-dry turnovers like easy interceptions or clear strip sacks and recovery. They've done a good job of making the touchdown reviews fast and painless for the most part (if they even review the easy ones), so hopefully that trend will continue.
If I read the article right, it looks like the replay thing will be exclusive to the fans in the stadium and not something that will be available on TV coverage. TV already has its share of replays and analysis, so they don't really need exactly what the referees are seeing but it'll definitely add to the stadium experience by showing exactly what angles the referees use and how many times they rewind the footage, etc. It's certainly an addition to the experience, and it removes some of the annoying downtime from challenge calls.