There are three "Discussions" going on simultaneously about this issue. plus another on the MacRumors website. There is definitely an issue. Whether Apple realizes it or not I am not sure, but I thnk they do. They do stand behind the products, and it seems that once someone at Apple are actually takes ownership of the issue the customer gets good service. I certainly have.
So far they have replaced my bluetooth module, replaced the internal antenna, and replaced my Mac Pro; none of which solved the problem. They have now set up an appointment for me at the Apple Store to have one of their technicians actually observe the problem. They are telling me that the Apple engineers are now claiming it's an "environmental" problem, i.e. interference from some external source, peripheral, etc. I'm quite sure this is not the case because I have twice disconnected the machine, brought it to a room with no electronics on the other side of the house, and the same problem persisted. Meanwhile, my iMac G5 does fine in the same place (on my desk) that I have my Mac Pro.
If we want this issue resolved sooner rather than later, the product specialists at AppleCare have to get the calls and then in turn notify engineering. Just because there are so many people posting these complaints on various bulletin boards doesn't seem to legitimize the problem as far as Apple is concerned. I am watching everybody go through the same process as I have, all with the same lack of success: new bluetoth module, new antenna, new Mac Pro. Call AppleCare, get to a product spcialist, and request they get the issue to engineering.
Interestingly, I notice that the Apple Store online has stopped selling the wireless Mighty Mouse. Maybe it works with iMacs and laptops because it is always right next to the computer, but when the computer is further away it soesn't work. Hmmmm.