no official CWA press release yet, but here's the union's:

Workers at Bethesda Game Studios have joined the Communication Workers of America, forming the first wall-to-wall union at a Microsoft video game studio. The workers, consisting of 241 developers including artists, engineers, programmers and designers have either signed a union authorization card or indicated that they wanted union representation via an online portal. Microsoft has recognized the union.

and here's their Twitter account