Hi Harry,
That is true. I confirm that there are purple buildings and blocks on the Imagery.
One thing to mention though is that there are images over the area that come from different seasons - white&black images were gathered during the winter time hence white color of snow. But I guess you've already figured it out.
Thank you for reporting this problem. We are aware of the issue and are working to resolve the problem.
Thanks,
Mike
Mike and Alexey,
I also encountered what I think is related to the above. I included the code as to make sure I had done things correctly.
http://forums.arcgis.com/threads/101937-Zooming-not-working-on-World-Imagery-Map