Anyone who has an Atrix with the call quality issue will find out pretty rapidly (assuming they talk to someone on it). You sound like you are talking with a rag in your mouth. Voice is very muffled. Turning noise suppression helps a lot, but does not clear it up. It still sounds very very bass, having little treble. We exchanged my daughter's phone, and the new one sounds fine. Mine was better than hers from the beginning, and with noise suppression off, it is usable.
Those thinking that the problem is just AT&T's network, or thinking the problem is in the head of those who have been reporting it, are wrong. The problem is real, and it is a significant issue. Fortunately, it seems like only a minority of the phones have the problems. Otherwise, the Atrix would have been DOA.