@Asbo Zaprudder, if nothing else, check out the new extras for the blu-ray release. It's still pricey, but the new bits and interviews almost make the purchase worthwhile on their own - particularly if one is a hardcore fan. I thought it was fantastic seeing Tom's companions (and Philip HInchcliffe) sitting through his season 12 stories and commenting on them.
I watched Robot on the blu ray set. I was very impressed with the improved image quality. I wasn't expecting the difference between the DVD and blu ray to be that noticeable given the source material. A very nice surprise!
Neither was I and I knew there would be two improvements upfront after finding out the disc count- the lack of MPEG compression and improved sound. What I didn't expect was a FPS drop (it's closer to 24FPS filmic than fluid videotape (25FPS PAL or converted to 29.97FPS NTSC)), but the slight FPS drop/film effect would have been necessary for the deinterlacing process anyway, which looks
phenomenal (even the most glaring examples don't look as harsh as one might expect) and is easily well worth the small tradeoff. Looking at the footage, I suspect they may have done some color enhancement. The edge sharpening halos are still a leftover from their initial remastering, but it's nowhere near as soft and jaggy as the upscaled TNG-R SD scenes were, moire is surprisingly limited given the circumstances, no chroma bleed, color saturation is fantastic, and the lack of visible compression blocks is a step up in of itself.
And I'll say this: Compared to the DVD release, the Cybermat scenes where the prop was in front of a CSO screen were much more convincing; harder to detect the difference between prop and background. The RT may have been doing something else to make the Cybermat prop blend in better but it looks great either way.
I still want to go back to the DVD and compare screencaps, since I'm that pedantic. But either which way, hardcore fans will want to double-dip and there's never been a better time to go Blu-Ray.