After plenty of community input, ArenaNet has published an update on major upcoming changes to World vs. World in Guild Wars 2. From population issues to the matching systems, to alliances, there will be multiple phases of changes designed to improve the experience in ways like addressing population issues and improving quality of life functions. Even just feeling like the WvW base feels valued and can trust that improvements will not only start to happen soon, but that their feedback really matters.
The first phase of the beta event for World Restructuring will happen from September 24th to October 1st. World Restructuring means that the current shards will cease to exist as worlds/servers. They will be called teams and a new matchmaking system introduced that will assign players, guilds, and even alliances to those new teams. These reassignments will happen on an ongoing regular basis, to better reflect population changes over time and that also have ways for groups that want to continue playing together to do so.
These teams will be destroyed and reassignments happen at the beginning of a new season. Seasons will happen at regular times that haven't been determined yet, but the team says it may last up to eight weeks. Active WvW players who don't pick a team on their own before the season begins, will be matched to one.
However, this first phase is only a beta event, and after October 1st, things will revert back to the current system. There may be more testing, but the beta is intended to provide data for the full implementation.
The second phase is a planned change to Alliances. The maximum player total will be capped at 500, which matches the size of a single guild. This effort is meant to try and balance players who want to remain together, and who may have been together for many years, and those who might want to create massive alliances to steamroll others, especially in light of population balance needs.
While the changes will be a restructuring as noted, the plan is to introduce the actual changes in small bits for beta testing in order to both let players get used to the shift and for the team to gather data on how to best go about this very big change.
For more, check out the full rundown on the Guild Wars 2 site.