I too was excited when they came out with the varicella vac. But that didn't protect my sons from getting the chickenpox, and they both had the vac twice also.
I was talking to my neighbor about the flu shot (he has two daughters in elementary school). The bad thing about getting the flu shot in August (this is when school starts here), it will be a hit and miss thing, because at that month they do not know which strain of flu will be the one affecting people. Those were his words.
Before anyone calls me one of those people who are against vac, this is not the case. Both my children had all the required vacs. I'm just opposed to forcing people to get the flu shot, from my own personal experience with it.