you'll probably have to wait on Manga to give you a good answer.
As far as I'm aware, Apple doesn't use AMD's fglrx driver, rather preferring to write their own driver using the X.org documentation.
Also, as far as I'm aware, the new Imac's are the first time Apple has used the RadeonHD 5x00 series cards in a production system. It's quite possible that there is a memory leak or other error in the relatively new Apple graphics driver.
The only things I could really tell you to do are:
File a support ticket to NCSoft: http://us.ncsoft.com/en/support/
File a bug report with Apple: http://bugreport.apple.com/
pop transgaming on the nose with a cider enablement issue: http://www.transgaming.com/contact-us
My suspicion is that it's probably a memory leak or buffer error with Apple's drivers. I have not experienced this particular problem with either X.org ATi or Fglrx under Cedega.
It does indeed have a Radeon HD 5xxx card.
It doesn't do it with no other programs loaded, but when other programs are run it does the weirdness.
I'll wait to see if Manga has any answers. Kinda frustrating with her having a new machine (a few days old) and both of us excited to play Going Rogue..
*also loading iTunes before hand does not fix it. When she switches songs it does it. It also errors out with Safari and also with Photoshop. Not all at once. Any one of them.
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This is an ATI issue, and the devs have been previously notified - but you might want to send a note to help.ncsoft.com anyway in case they forgot. 
You will have to experiment a bit to fix the issue. For instance, try using Cmd-Tab (minimize) instead of Cmd-Enter, or set to a lower resolution and play in windowed mode all the time, or try typing /reloadgfx and hitting Return before you switch to windowed mode.
Turning off Geometry Buffers will reduce the amount of crashes and lag, but it won't eliminate it. Try using /reloadgfx every hour or so.
Also, the F7 thru F9 keys on newer Macs control iTunes without having to switch away from the game (F10 for mute, F11 and F12 for volume).
Manga @ Triumph
"Meanwhile In The Halls Of Titan"...Titan Network Working To Save City Of Heroes
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Has this issue been resolved? I am thinking of buying an iMac this week but will hold off if CoH/CoV/Going Rogue doesn't work correctly.
Thanks!
Don't know yet, only the devs know.
Manga @ Triumph
"Meanwhile In The Halls Of Titan"...Titan Network Working To Save City Of Heroes
Save Paragon City! Efforts Coordination
Thanks! I was going to get an iMac but read one of your posts that the graphics card could not be upgraded.
My girlfriend just got the latest and greatest 27" iMac and was looking forward to better performance, and lack of crashes in Arachnos bases.
However now after playing for a while if she goes to windowed mode temporarily to check iTunes or something, when she goes back to full screen she gets the screen as just solid colors. Sometimes the colors may switch as a whole, but basically is still a solid color and she's essentially blind while in full screen.
Windowed mode works afterwards but to have full screen work properly again she has to quit and restart the game.
She deleted the preferences and turned off 'Use Geometry Filtering'.
Any ideas?
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