ABAVETTA  Simple, works, bomb proof (temporary, I hope) work around solution to long backups. Here is what I do.

Because it is safer to have iTunes closed when changing it's preferences I use the following procedure.

1) Close iTunes

2) Open Backup Disabler (if not already open).

3) Toggle Backup Disabler to the desired state.

4) Open iTunes

5) Close Backup Disabler (optional)

Whenever I feel it would be prudent to back up my iPhone I enable back up and let the process run overnight. Who knows how long it takes but it's always done by morning, Otherwise I have backup disabled when I synch my iPhone.  
(Version 1.3)