Apple OS 10.4.3 update
If your video is driven by:
ATI video card: You may see extreme cases where dots follow your cursor when using tools like the Pencil tool in larger models. Or you may see things like lines that are drawn by the tool don't seem to be at the right depth. In both of these cases, the issue can be fixed by turning off fast feedback: SketchUp pulldown menu -> Preferences -> OpenGL -> uncheck "Use fast feedback".
nVidia video card: You may be unable to see geometry as it is drawn in large models until after the drawing action is complete (e.g., no rubber band stretching of an edge with the Pencil tool). This issue can be fixed by turning off fast feedback as mentioned above. You may also not be able to see the selection boxes when using the Select tool. Unfortunately, the only fix for this issue is to turn off your video card's hardware acceleration: SketchUp pulldown menu -> Preferences -> OpenGL -> uncheck "Use Hardware acceleration".
These are the issues which have come to our attention, but there may be other problems. Unfortunately, the Apple update has caused problems for a number of other applications that use OpenGL. @Last is working with Apple to hopefully have Apple issue a fix as soon as possible. They are also exploring issuing a new SketchUp release to provide a workaround to the nVidia selection box issue. In the meantime if you have not already updated to OS X 10.4.3, @Last recommends that you refrain from doing so temporarily.We apologize for any inconvenience this may cause and please let us know if you have any questions or concerns.