The Mini BD units are recordable and rewriteable, and aren't all that different from other optical media in terms of fabrication, though it does include Verbatim's anti-scratch coating:
The proprietary hard-coat finish on Verbatim BD media has superior anti-static and anti-scratch properties for added protection against scratches, fingerprints and dust particles that can occur during normal camcorder and home use.
There's no mention if Verbatim also has plans to fab Mini HD DVD media. There's likely not much of a market for Mini hi-def media, but that will change when camcorders capable of taking such media begin making their way to shelves. You can read the full press release on Verbatim's site.