As it seems, that no-one has any info regarding changes/differences with these FWs, I installed the EU-version. Been using it without any problems since. Earlier with WW-version, my Xbox (new S-model with N-wireless) dropped from net once. Though I cannot say, was it because of ww-firmware or some other thing (Live-problem), it hasn't happened again with EU-firmware. Everything I use, works just fine, so I'll be using the EU-version.