We have yet to see if HL2 will become a success, at least a success compared to HL, people still play HL to this day. Not everyone is going to move over straight away but will everyone move over and stick with it like HL in 6 years to come.
The reviews do say its good and everything but the majority have yet to experiance it. That aside. Congrats to Valve for finishing the game and doing it through all the shit some people have put them through. Now lets get the real MP out in other words lets get TF2 out. Hopefully magazines will be saying, "You thought HL2 was good, you thought CS was good, wait till you play TF2"