Past experimental data have narrowed the range of possible masses for the elusive Higgs Boson to lie somewhere between 120 and 150 GeV. Scientists at Fermilab now believe they will have enough data to close this window completely by the end of September. Although it will take months to process the data, it should reveal with certainty if the Higgs Boson exists or not in the mass range where the standard model predicts it must exist. If the Higgs Boson is not found in this mass range, then certainly something must be wrong with the standard model. Other theories exist that could explain electroweak symmetry breaking, but if any of those theories were correct it would imply that the standard model is not correct. Either way the results will be exciting. The questions should be settled one way or another by the end of 2012.
But, will the Large Hadron Collider find the Higgs Boson, or disprove it's existence, before Fermilab? The LHC is currently on a technical stop, so they will not be able to collect any data before Fermilab collects the data they need to close the 120 - 150 GeV window. But it will still take months for Fermilab to crunch the numbers, and anything is possible in the meantime.
One way or another, 2012 is going to be an exciting year for particle physics.