My suggestion – wrap up the stuff that you want to and make that 1.2. Sure, it’s a jump from 0.2.4, but it will be necessary to sync with the Roku numbers at some point, and the forum messages indicate that many users look to whatever is hosted by Roku as an “official” version.
Then look at UPNP. If other stuff fits in with that then that could be done in parallel, but I feel there is significant demand for a UPNP server with the stability and footprint of Firefly, so make that 1.3. That would also appeal to some of the NAS vendors, who often ship with relatively limited UPNP implimentations. The Mac stuff, plugins, etc, are all good, but for me at least would be part of a 1.4 release.
Just my 2 cents.
Thanks for asking,