I'm pretty sure people won't commercially market copies of the existing BFG ships. GW still has copyright over their exact designs, so doing anything large-scale would pretty much be asking for a lawsuit. That said, I suspect there's a pretty good chance that third parties might step up to the plate and try to provide non-infringing alternatives that still fit the theme and feel of various fleets.
I mean, small shops have been turning out alternative Blood Bowl models for years, and Mantic's pretty much remade that game in all but name. Epic: Armageddon would be tough, but with spare plastic infantry lying around it's pretty easy to proxy imperial, chaos, or ork vehicles with something like GHQ's model ranges. As for BFG, between 3-D printing and the relative ease of creating rubber molds for resin casting, there's a pretty good chance that die-hard fans of BFG will try their hands at creating alternative ships of their own. Heck, some have been doing this for years already.
The real question is whether GW will feel it's worth going after any of the small-scale alternative model producers now that they've killed the product line. I figure Chapterhouse Studios has most of their attention at the moment, and the outcome of that case will provide us with a pretty good idea of what's legally permissible in the States at least.
