Good question.

In both versions I've had (2.0,4.0) the returns from (Get-Host).Version, $psversiontable.PSVersion, and $Host.Version have been identical - so perhaps from version 2.0 onwards the powershell version and the ConsoleHost versions have stayed in step. I wonder if that's deliberate and will continue to be true?

Anyway, I got it wrong because I thought they both meant the same. Using $psversiontable and $host instead of the two level things delivers much more information, and was a revelation to me today when I discovered it from one of the comments on this question, so I've learnt something potentially useful today. But I don't like the answer to the question, since it gives me "build -1" instead of a real build version and doesn't tell me which version of the remoting protocol it uses or the versions of other interesting things the way the shorter version does.