Is the "dust problem" in reference to dust getting trapped between the glass and the LCD panel? If so, it's solved since the new LCDs are laminated to the glass, and do not contain an air gap to collect dust in.
Funny thing though... my 2007 iMac has never had any dust get trapped between the glass and the LCD, and I consider my office to be pretty darn dusty at times. Maybe the models between 2007 and the new 2012 are more prone to dust issues. 😕