The new combined CDF/D0 Higgs mass limits are out, there’s a paper here. At a confidence level of 95%, a standard model Higgs is excluded for a mass range between 160 and 170 GeV. At a confidence level of 90%, the range excluded is 157-181 GeV. Precision electroweak measurements already constrain the Higgs mass to lie below 185 GeV (at 95% confidence level).
Taken all together, it now looks likely that, if there is a standard model Higgs, its mass is in the region 114-157 GeV. With the data they have analyzed so far, the Tevatron experiments are only able to say that the cross-section for producing a SM Higgs over this mass region cannot be more than 2-3 times the SM value. They still have more data in hand to analyze, and the machine continues to run well. It will likely stay in operation at least a couple more years, possibly doubling the number of collisions already collected. The paper promises:
The sensitivity of our combined search is expected to grow substantially in the near future with the additional luminosity already recorded at the Tevatron and not yet analyzed, and with additional improvements of our analysis techniques which will be propagated in the current and future analyses.
Now, we just need to hope that they don’t find the SM Higgs in this remaining region, which would make things really interesting…