Just uploaded a new build (mplayer_1.0rc1-maemo.5). It contains only a minor tweak which eliminates any need of rebooting the device after installing mplayer package. So now installing mplayer is just as easy as it was before

After playing with these new versions a bit more, I think that it is quite good and if no problems get reported in the next few days, it will be promoted to 'stable' and uploaded to garage extras repository. So feedback is very much appreciated.