It is the 1/568 scale Modelcraft Queen Mary kit (any film fan worth his salt knows that the Poseidon was actually the Queen Mary.)...
I didn't scrutinize the details (such as perfectly filling seams and filing flash) as I figured in the relatively small scale it wouldn't be totally worth it. But this is a deceptively nice kit,a nd builds up quite well.
I still have quite a bit of detail painting to do, but will post more pics when done.