Pipeline changes could slow Intel's Prescott down

Taken with a grain of salt.

As long as we dont see another willamette its fine with me, the improved HT should prove usefull in everyday usage and the 3.4-3.6ghz could probly makeup for the added stage. Hopefully at least...

It depends on what they're changing (in the pipeline). Lengthening the pipeline in and of itself does not a higher clockspeed make. If the changes are a redistribution of pipeline functions, then it should facilitate clockspeed, but it's to add new functional stages (such was the case with the K8's 2 additional integer pipeline stages), then it really won't help clockspeed at all.
Also, branch mispredict penalties would also depend on what the new stages do (whether they're redistributed or new functions). If they're new functions, and the integer/branch pipeline does not use these, then there is no added branch penalty. The FP pipeline, and FP operations in general, usually have very little branching.

"We are Microsoft, resistance is futile." - Bill Gates, 2015.