A post on Battle.net outlines plans to bring an improved replay and observer interface to Heroes of the Storm, saying this will be closer to what's been previously seen in the BlizzCon World Championships for the MOBA. They say this will be replacing the default interface "very soon," but for those who cannot wait, they offer the chance to download and check it out now, though they say this probably won't be the final iteration before it is officially launched. Here's word:

Greetings, Heroes. We’ve been working closely with community member Ahli to create a new interface for watching replays and observing matches in the client. Some of you may recognize a lot of these new features from an earlier version we used at the BlizzCon World Championships. While this probably won’t be our final iteration, we wanted to get this version into your hands now as this new interface will be replacing the default replay and observer UI very soon.

With new art, talent icons included in the top bar, and collapsible detailed stats and talent panels, we think this interface will introduce an exciting new level of easily-digestible information to players looking to analyze games as a spectator or through watching replays. You can also look forward to even more features coming with the interfaces official release and beyond, including current Map Mechanic counters for each team on maps like Blackheart’s Bay and Tomb of the Spider Queen.