Motion JPEG 2000 (MJ2) is one potential format for longterm video preservation. The format is attractive as an open standard with a truly lossless compression mode. Currently, three software-only MJ2 implementations are readily available, from the Open JPEG 2000 project, from the Kakadu project, and (incorporating Kakadu) from vendor Morgan Multimedia. These are given a snapshot evaluation here. Among the findings: on a modern desktop machine, the Kakadu-based implementations can decode and deliver quarter-screen or smaller lossless-MJ2-encoded videos without frame drops. The newer Open JPEG 2000, while improving, is not yet competitive. All the implementations have practical limitations on acceptable input formats, and inadequate or missing audio support. At higher image resolutions, playback without frame drops or reversion to lossy mode currently suggests hardware-based implementations. A practical impediment is limited availability of off-the-shelf board-level products. Competing candidate file formats for video-editing, archiving, and delivery currently offer better-defined storage of metadata. Some formats, such as MPEG4/AVC, achieve better compression at the expense of some lossiness.