As with all rumors, please take the following news item with a grain of salt until we can receive official confirmation or denial from AMD.
As we've previously reported, AMD is rumored to be shipping their B3 stepping Phenoms, and it seems that we might see 2.5GHz models before April Fool's Day:
“AMD is planning to launch B3 stepping quad-core Phenom 9050 series CPUs including 9850, 9750, 9650, 9550 and 9150 within the next 1-2 weeks, however the top-end 9850 will only reach a core frequency of 2.5GHz, instead of the original goal of 2.6Ghz. The company expects to be able to deliver higher core frequencies in the third quarter this year, according to sources at motherboard makers.”
While a 2.5GHz Phenom isn't likely to wrest the high-end CPU performance crown from Intel, but it could certainly spark a decent performance/price battle in the mid-range if it were to come in at an affordable price point.
If you're waiting on Tri-Core Phenoms, you might have to wait a few additional weeks, but they're expected to be appearing on store shelves by the end of April.