As far as I can see the released ports of the P.E.Op.S. gpu/spu sources are free of any XDK copyright issues, so I can give my OK for the ported plugins. Of course linuzappz (main coder of pcsx) has to give his OK for the ported main emu as well.
On a sidenote: I like ports. There are many ports for my psx plugins available, for all kind of systems and operating systems. But usually I get asked before someone is releasing binaries from my GPL'd work. And this didn't happen at all this time, so of course I started to wonder what the hack is going on.
So, as long as only the plain sources are available to the public, without 'bundled' XDK libraries, or illegal compiled binaries, I think the GPL is fulfilled.
Nevertheless I will not get tired to mention that the xbox scene would be a much more comfortable place for hobby coders, if the scene would stop to press on illegal binaries (using the XDK), and concentrate on a free and legal XDK alternative first.
Last but not least: imho, a xbox is not fast enough (cpu-wise) to run all psx games at full speed with a soft gpu plugin like the P.E.Op.S. one. And activated frameskipping will cause jumpier displays and compatibility issues like missing battle screens or other glitches.
So, without an hw/accel gpu plugin (which, of course also has its compatibility issues, but a much better speed and improved graphics), the xbox psx emu will be not a real replacement for a PC psx emu (or, of course, a real psx console), I think.