There may have been a bit of conjecture involved, but taking into account that for the prequels, absolutely everything was filmed and documented and retained (for behind the scenes content & documentaries etc) and that we know of a few scenes from the PT that were left out but do exist (the lost 20 scene springs to mind) then there must be a lot more that didn't make it.

Every film out there has a ton of content that doesn't make the final cut, and based on the fact that two of the prequels were filmed digitally and they therefore can't use the excuse that it's degraded over time, then we're looking at probably hours of unused footage.

Also, I think you're forgetting that none of the deleted scenes from the PT DVDs (which are numerous) are on the Blu Ray set at all. So I'm probably right on the money.

If you were referring just to ESB, then we've got our wires crossed. I was meaning the deleted scenes in total - because if this was to be a feature in each revisited release, what's lacking in terms of deleted scenes with one film will affect consistency between the others. And I'm all for consistency ;-)