I'm sure people play games like LEGO Star Wars(Plastic vs. Plastic battles. =P) anyway... And you might have a point, but I'm sure LEGO'd have some sort of parental controls for that.
And while it would get people to buy it; isn't the same able to be said for any MMO? If you add PVP in, it automatically gets more players, who want to play something like that, since they could run out of things otherwise.
There is one thing, however... The fact that one of the pre-release screenshots had a picture of PVP in it. And it looked like it was on the Venture Explorer, from what we know now.
