According to Giovanni Punzi, a member of Fermilab's CDF collaboration team, we're not at discovery yet, but we're getting tantalizingly close. The first results were generated using 4.3 inverse femtobarns of data; we're now up to 7.3fb^-1, the peak is not going away, and the results are now closer to the five standard deviation standard. In addition, the detector team has gone back and eliminated some alternative explanations, like background from top quark production.
Yeah, I definitely had to go look up what a
barn is; I didn't learn that in school. A new particle would be cool, though.
[Update] Tevatron's second detector shows no sign of the new particle after
analysis of its results.