Never seen the point of partitioning single drives (well since the days of DOS, and addressing large volumes being an issue).
For me, it would be one 1TB volume.
Actually, no, for me it would have been 4 250GB drives shoved in a RAID 5 array.
I dont like big drives for the reason if they break you loose, potentially, a lot of data. I'd rather rely on 3-4 drives. But if I did have a 1 TB HD i'd divide it up, defraging none system files is a waste of time and a full 1TB drive would take eons.