Have not seen even the slightest hint of macroblocking or any other artifacting on the European release of Sweeney Todd, nor have any reviews. In fact, by all accounts, including my own eyes, "Sweeney Todd" is an impeccable transfer, and one of the finest on the format. THAT, and it comes in a really beautiful steelcase.
Check out the third post. Now, I have the UK release, but I haven't watched it yet. I'm still waiting for a good time when the wife and kids aren't home to crank this sucker. That said, I doubt I would notice the macroblocking, if it is indeed there, as you really have to look hard at that picture to see it, on my relatively small (50") display.
As far as reviews go, and this is really delving off-topic, but, suffice it to say, the number of reviewers I actually trust seems to dwindle with each passing day.
I have the UK BD release. It is the first time I have ever imported a title of any sort.
It is awesome. The soundtrack and picture are both divine. I, however, have an extremely small HD display so most PQ concerns aren't really concerns for me at this point. But, I cannot imagine the soundtrack sounding any better. What a treat!
My favorite part of the UK packaging is the blurb on the bottom of the front cover: "...a bleedin' masterpiece!"