Gioga23 notes [Google translation] that the iPhone 3G and iPod touch, despite not having built-in video cameras, are able to utilizing the iPhone 3GS video trimming feature when running iPhone OS 3.1.
E-mailed videos can be saved to the user's Photos application, where they can then be opened, trimmed, and saved as edited copies. While the feature's utility is somewhat limited due to the devices' inability to shoot video, it could see some usefulness for users who receive a video clip while on the go and would like to pass a shortened version of it along to others.
Article Link: iPhone 3G and iPod Touch Gain Video Trimming Capabilities in iPhone OS 3.1