from my knowledge, we should always look for bigger capacity per-platter
as it improve the speed
i think 500GB and 1TB is same, reliability wise
although not the case for 2TB/3TB, which seems high enough
nowdays 500GB drive usually use 1platter - 2 head
640-1TB use 2platter - 3-4head
but back on your usage
if you using for OS drive and thinking to put your data on another hdd
then getting 500GB better option
but considering price getting 1TB for OS is not bad either, as you got extra space, and if you play game, you know game nowdays take lots of data too
+1 to DirkGently1
people saying samsung drive (F3) is fast, and i been hearing lots good comment from samsung drive, even haven't test it myself (thinking too get some drive soon)
and i think the drive will available at least until 2012, even WD already bought samsung, but such big company transition would take some time
@wayliff
that news is from 2009
i think current seagate drive (Barracuda 7200.12) already free from firmware issue
WD Black Caviar is fast too, some saying that its good for OS drive as its have faster access time, but in realworld seems user wont notice it plus the price is a step higher to average price...
i am WD Black Caviar user, so far i am quite statisfied with the drive
for Seagate, i am use some seagate drives, and got no problem either