As a physicist, i should be excited about this new LHC, but i dont give it a damn anymore... what if they find the higgs boson? What will it change in my life, or yours, or everybodys else, for this matter? The only who will profit with this will be the few scientists that work there, which probably will win some nobel or something like this... but for us all, the world will keep being exactly the same, with higgs or without higgs.
I dont think they will create a black hole, but even if it happened, it would evaporate instantly, so we dont need worry about it.
And the LHC energy is not enough to enter "other dimensions" and things like this... But even if it were possible, still it would be completly useless. If they need a machine with dozens of miles to "open a door to another dimensions" with the size of a subatomic particle, how great should be the machine for make this "door" large enough for having any practical use?
Im pretty sure the world would be far more benefited if they take the money they wasted to make this enormous thing and used to fight the hunger, the poverty, and such...