Theshigen writes “Smoother and more stable performance. Thats the promise of the incoming 64 Bit update for Company of Heroes 2 on Steam. The update was supposed to have released much earlier, but a new update from Relic revealed that there was a major technical issue they have found that needs ironing out.”
Source: N4G PC Company of Heroes 2 64 Bit Update Will Release In Late November Frags of War