I have the same situation with my 1T Maxtor One Touch III drive as others have described. I just received my warranty replacement, but, like you, having a four month old drive die is not my idea of a good backup solution. Like the other people, the drive just started that horrid clicking sound and then it was gone. I tried trial copies of three different OSX drive recovery software, but not a single one gave any hope of recovering anything.
My two year old 400 G Seagate Firewire 500g and Firewire 300g drives are still working fine.
Over the last several years, nearly every Maxtor drive (both PATA and SATA) that I have owned has quit with the exact same symptoms. Thus I can only conclude that there is a design flaw with the Maxtor drives. While I don't know if this particular unit has Maxtor designed drives or Seagate drives, I have made the decision to never again buy anything with the Maxtor name on it.
The jury is still out whether the replacement drive will die like the others, but I won't count on it.
Furthermore, I cannot get the One Touch function to work on Leopard despite the fact that I have now carefully followed the instructions twice. Maxtor/Seagate have not updated the instructions for Leopard and probably won't.
This is my last Maxtor drive.