Google recently updated the Voice Search app for Android, giving users the option to setup personalized recognition. With the feature enabled, Voice Search remembers words that were searched for and associates them with your Google account. The goal is to improve the accuracy of voice search and enable users to search faster.
This update is only available for users running Android 2.2+, and currently only for English in the United States. Although Google stated it has plans to support additional nations and languages in the future, however no timeline has been given. Be sure to download the update from the market today! (via Google)