P: PDF import show edge artifacts on tiled PDF images (bug in PDF creation)

Thanks!
I'll keep this thread bookmarked.
Looking forward to hear some good news from you regarding this quite monumental problem.....

We're still working on it - but don't have any ETA.

Thanks for the comprehensive answer!
So, what is your appraisal? How is this problem classified in your priority list.
I just want to understand, how long it will take you to develop a fix (however this will look like).
Problem is, that our customers use CS6 more and more (which is good for you, of course) - so I'm a bit in a situation here.

No, we moved to the new antialiasing partly to avoid several problems with the old antialiasing method. Photoshop CS6 is rendering the files correctly, but they are not written in a way that can be antialiased correctly except at resolutions higher than the original image resolutions. And we've tried to work around the bad files and find a way to render the images without artifacts - but everything we've tried has failed.
We can't go back to the old, broken antialiasing - and the only thing causing problems with the new antialiasing are tiled images in some PDF files written by some applications. The only way forward is either to come up with a way to fix the tiled images, or to fix the way the images are written into the files.

Interesting - I will make some tests to get the picture...
In theory I can follow your arguments, and belief me: it's good, that you increased accuracy of the PDF rendering. So much for the scientific approach. But what should I do in real life, what should I tell my colleauges at work. They solely see the results they get using CS5.5 and CS6. Isn't it possible to integrate a switch in Photoshop CS6, where you can choose between the old method (used in CS5.5) and the more accurate new one?
I understand, that the most satisfying sollution for you coders and programmers would be, to solve the problem on its basis (the tiling process in, e.g. InDesign). Everything else is a regress.
But I tell you: sometimes you have to take a look through the customer's eyes. For us only one thing matters: what comes out at the end, fighting with the customer's data.
As long as this problem isn't solved, I don't think I can give my "go" to the upgrade to CS6.

Again, it doesn't. Photoshop CS 5 and earlier just handled the antialiasing differently (using higher resolution and scaling down) - but that was slower and less accurate than the antialiasing in CS6. If you spend some time testing it (like we have), you can find the same artifacts in CS 5 and earlier versions as well.
Again, the problem is in the documents with tiled images -- someone did not think through the implications of rasterizing those documents at any resolution less than the original image resolution.

Then why does Photoshop CS5.5 do the job? Besides: I rendered the PDF file in several resolutions - result is always the same.

Unfortunately Photoshop can't do much about the misformed files -- we're still trying to get to the bottom of why the files are written badly in the first place.

But as long as the images are written in tiles, they will have artifacts with antialiasing at any resolution below the original image resolution.

We are in printing business, too. The upgrade to Adobe Cloud CS6 is stopped, because of this issue. After I read this thread (and saw how long this is known by Adobe with no action taken) I'm feeling vindicated in supporting the upgrade stop.

If they are putting out tiled images, then yes - because they cannot be rasterized correctly with antialiasing or at low resolution.