The beta release (available through a special version of Overwatch) will focus on the World Cup, but Blizzard hopes to make the technology available for all gameplay types on all supported platforms. You could analyze a friendly match between friends if you wanted, similar to what you can do with titles like League of Legends.

Just be sure to temper your expectations for BlizzCon. While there will be "awesome" announcements when BlizzCon kicks off November 2nd, new maps won't be part of it. The biggest official change outside of the World Cup Viewer is word that Mercy, Reaper, Roadhog and Symmetra will all receive improvements for the 1.30 patch. For now, the World Cup is the focus.