The 7D at 3200 looks the same as the 1D4 at 6400. Online samples show this (i.e. Imaging Resource) and direct numeric measurements of both JPEG and RAW confirm it (DPReview). The 7D is actually slightly better at 3200 than the 1D4 at 6400, so if the 7D is unacceptable at 3200 then the 1D4 is unacceptable at 6400.
Have you even used a 1D4? Don't talk in your dreams, 7D has the highest noise in all APS-C cameras, ever. Any sensor will beat that piece of crap 7D sensor.
It shows bad noise in ISO 100! Who are you kidding, take a landscape shot with tripod and ISO 100, and it can be full of noise! Oh my Jebus! 7D fans are either ignorant, or in denial that is for sure.
If you only read camera specs instead of actually using them, you should also know that while 7D does ISO 12800, 1D4 does 102400. Does it mean that 1D4 is 3 stops better than 7D? Maybe!
Following posts discuss 7D ISO 100 noise issues, if you love your 7D, don't look
http://photography-on-the.net/forum/showthread.php?t=896611
http://www.flickr.com/groups/canon_eos_7d/discuss/72157626132771753/
http://www.fredmiranda.com/forum/topic/879150
Noise at ISO 100 and Noise at ISO 3200 are very different things. Canon's APS-C sensors suffer from high electronic noise at low ISO, where as Nikon and Sony sensors control electronic noise better there. Once you are beyond ISO 400, however, the physical nature of light begins to dominate, and noise characteristics normalize. There is actually not much that can really be done about high ISO noise, particularly from ISO 1600 and on. Larger pixel wells and higher quantum efficiency allow you to gather more photons, which improves SNR...but once your up to 3200 and 6400, its a matter of time and light volume...there is VERY LITTLE difference between any camera at these levels (from an electronic, hardware standpoint). The key thing that matters is photon conversion rates...how many of the photons reaching the sensor are actually converted into charge in each photodiode. The 7D has a 41% Q.E. while the 1D IV has a 44% Q.E...that gives an edge to the 1D IV, but the differences at high ISO are not going to be very large...possibly noticeable, but not large.
Additionally, ISO 12800 in the 7D is an "artificial" ISO, digitally amplified. ISO's above 12800 on the 1D IV are also "artificial" and digitally amplified...so they are not really higher ISO settings. They amplify noise, both color and lumi, along with everything else, and you have some serious IQ degradation at those settings. Your far better off under-exposing at the maximum native ISO setting and correcting in post where you have full control over that digital amplification.
Before you go around calling people ignorant, make sure you aren't ignorant yourself.