Pretty much everything I've read on ANN/AoD about the US Samurai Champloo DVD release indicates that
1) The show was digitally animated in SD, so the BDs are upscales. (Meaning that the gain is questionable in 720p-rips, let alone 1080p)
2) Funi went overboard with digital noise reduction and other filtering during the upscaling, meaning that the BDs look
worse (less detailed) than the DVDs.
I'd expect the same problems to carry over to the BD-rips.
One source:Samurai Champloo is an upscale, and they went way overboard with noise reduction. It actually has less detail than the original Geneon DVDs. It might look sharper or crisper to people because of the edge enhancement, but as far as I'm concerned the video is a downgrade from the DVDs, though the audio is an improvement.
So basically, comparisons should also be done with the DVD-rips upscaled to 1920x1080 to see if there's actually anything gained in the Blu-Ray versions. No point in having people DL bloated 1080p rips if player upscales of the 480p videos will look the same or better.