Mine is a Seagate
My 160G SATA drive (7200 rpm) is a Seagate, and it is original equipment Apple (my MBP was configured with a 7200 rpm drive from Apple). I had a Hitachi in a pc notebook (also a 160G drive) but it died and was replace with a Seagate (which is now my backup drive in an external case - I mirror the internal drive at least twice a month). The Western Digital drives seem ok too, and I have a 250G 5400 rpm drive in the pc notebook now.
If you can wait, there is a 500G drive (April) or the 320G 5400 drive now.
I have found little difference in heat or power with the new 7200 drives, and often the faster read times means more standby time for the drive as well. The 250G 5400 rpm drive does seem as fast for all but large file transfers, so I don't think the speed is that critical for day to day use.
Wayne