I agree. I was initially very interested in the new iMac, the design is fantastic, however the build quality leaves much to be desired.
The cheap white LED back lit screen will always be problematic and is an unchangeable component of the late 2009 iMac. The screen together with the high pitched whine problem, the flickering black out problem and the shattered glass screens preclude a rational consumer from even considering an iMac at this time.
Hopefully, Apple will improve the iMac over time. In the interim there are more compelling computers on the market. Specifically the Dell XPS 9000, together with the Dell UltraSharp U2410 monitor. Widows 7 is very stable and quite elegant, so unless you absolutely must have the candy coated Snow Leopard OS, I feel that the time has come to "dust our feet" from Apple and move forward.
While it is certainly true that the Vista debacle helped Apple in the short run, it is also true that Windows 7 is the Apple killer.
The late 2009 iMac is like a bad car wreck. The only thing left to do at this point is to move on and don't look back.
Oh, what might have been.