Why not both, the basic idea is having more variety in what we can use for menu backgrounds, whether that be:
- Random selection from multiple backgrounds.
- Gifs.
- Videos.
For video files, I don't feel a fade and what not would be necessary to implement as an effect applied by the osu client.
Not all video files are going to be great to use as menu backgrounds (as with any other skin element) and some may require you to modify them yourself by adding fades and what not (or at least make it optionally applied for those that are incapable of editing video files themselves), it shouldn't be something applied to every video within osu because some video files that people would like to use may already incorporate their own such effects.
