The Washington Post has announced the results of the 2010 Census for the District of Columbia. The GreaterGreaterWashington Blog has a very good analysis of the results.
The overriding question for Ward 3 will be what, if any changes come as a result of this count. On the one hand, it may be that any shifts in Ward boundaries may be surround only the wards which need to have population adjustments as defined. On the other hand, shifting borders in several wards may mean that all wards will have changes.
In 2000, Woodley Park was divided, with the portion east of Connecticut Avenue ending up in Ward 1. Similarly in Chevy Chase, the areas east of Broadbranch Road were moved into Ward 4.
The DC Council, particularly Jack Evans and Phil Mendelson, will have the most to say about this process.
EDIT: GGW has created an application that will allow one to test out different options. There is also an ANC feature.