We mentioned that CCP Games is working on thinning out Local in EVE Online's highsec trade hubs like Jita, but they're also looking into other ways of keeping lag at manageable levels, even if it requires taking temporary (and unpopular) measures. CCP Wrangler announced today that the latest downtime brought with it a new feature to Tranquility: EVE's stargates will check how many players there are in a given solar system and deny access if the system has hit its population limit. The temporary measures are presently being discussed on the EVE Online forums, with a few clarifications and amendments made by the devs.
There is some debate as to whether the pop limit affects Jita alone or if it affects all systems in New Eden, but regardless, the devs have stated multiple times that they're working to resolve the population issue. However, if the system population issue expands to other high traffic solar systems in EVE, this could stand to be a serious problem for the larger 0.0 alliances who rely upon their numbers to hold territory. The latest word from the devs states that only Jita is affected by population limits, and that a node crash is responsible for most of the 'traffic advisory' warnings players are receiving about multiple systems being inaccessible. These are some of the issues that can arise in an unsharded MMO, but hopefully the changes to stargates will remain as CCP states: temporary.
Update: A hotfix deployed during Monday's downtime removed the system cap from all solar systems except Jita, which now has a player capacity of 1024. CCP Explorer stated that the capacity will be raised over time as they make server adjustments. Ultimately they hope to remove the population limit altogether.