If it was a less powerful but still HD PS3 with Move but probably no blu-ray for $399 (probably still losing as much as the actual PS3 did at $599).
I'd say Wii would have gotten out of the gate quicker thanks to Wii Sports and a lower price point but PS3 would have caught up thanks to receiving upgraded Wii ports and downgraded, Move enabled 360 ports, making it the one system that rules them all.
Once it pulled into pole position, then all develop would have shifted to PS3 meaning 360 games would be identical despite it's superior power (like Xbox getting PS2 ports) and Wii would have downgraded PS3 games but not nearly so bad as the downgrade ports it had this gen, although Move is superior tech to wiimotes so the loss would not only be in graphics but motion sensitivity too, really helping PS3 be the obvious choice for all gamers.
PS3 would have been the dominate system like the PS2 before it, although 360 and Wii would have preformed better than Xbox/Gamecube.







