Yes, but only in the Mac version. Video files can be viewed and even played in the Preview window (Mac Only). You can choose which frame of the video file is used as the preview thumbnail by navigating to the desired frame with the video playback controls, then Ctrl-clicking on the video and selecting "Set as Poster Frame." You can save the current video frame by selecting File > Save Photo As. If you select a poster frame for a video, that is the photo that will be saved if you select multiple video thumbnails and then saving.
-Mick