Update: 1.21 RC0 is now available for Mac PowerPC
This is an update to the previous report and announcement about the 1.21 Release Candidate: We have been able to resolve the problem which causes an immediate crash for residents with a Mac PowerPC processor.
The download file for Mac has been updated. If you re-download the Test Viewer from our downloads page, it should install and run successfully on your PowerPC computer.
Discussion about the RC0 viewer continues here in the SL Forums, and on the Public Issue Tracker.