The next Amiga (or amigalike) system that I'll buy got to be able to play a fullhd movie on my TV being connected with a HDMI cable and from I've read the X1000 will be able to do that. I know that my PowerMAC never will.
You are just wrong. Today a PowerMac G4 already replays 720p vids easily (my 1.5 GHz Mac mini is pretty loaded with 720p, but actually does handle it nicely) . You want hdmi? Easy, get a hdmi/dvi cable and be done (hdmi is backward is compatible dvi).
The G5 does easily replay full hd, it has been tested already by Fab.
You see, your demand is fully covered by the rusty old el cheapo Apple gear with MorphOS. Part of your demand since about two years meanwhile (720p hdmi). But of course you may continue to wait for the holy grail....