@ Darth, I said 10k - 15k PS3 unit sale in another thread... but considering GTA4...
The sale of the GTA4 is actually interesting, when was the last time a game on the PS3 debuted to over 100k first week? (77k first day should mean 100k+ first week).
Looking at the sale pattern from that week for PS3 should give us a better idea of PS3 units being moved.