One thing that dianemo does not need to really care about, and which is holding LinuxMCE back a lot, are all the different hardware setups. Dianemo, afaik and please correct me if I am wrong, basically has its defined hardware and uses disk dumps for installs.
With the work done by Dianemo and LinuxMCE devs to get 1004 up and running, Dianemo took it even further into the later releases.
There is very little in the LinuxMCE codebase that is distribution specific. And most of the stuff that is, relates to setup and hardware configuration. Two areas, where Dianemo has the advantage of having a controlled environment.
We, LinuxMCE, need to provide a DVD image/network install script, that works on a lot of different hardware setups, and network layouts, and hence have much more work to do in the detection and configuration area.
Those are my 0.02EUR to the question.