After Intel's price cuts we mentioned that despite Penryn's imminent launch, CPUs had gotten too affordable to pass up building a system now if you needed. Now that we have a general idea of clock-for-clock performance differences between Conroe and Wolfdale, we're not nearly as worried about recommending that you build systems today as we once were. There's no doubt that Wolfdale is faster clock-for-clock, but keep in mind that you won't see Wolfdale until Q1 of next year and the performance advantage simply isn't great enough to justify delaying a purchase by 6+ months if you need a system now.

AMD seems quite confident that Phenom will be able to compete with Conroe/Kentsfield; if the race is really close between those cores, Penryn could be exactly what Intel needs to remain technically ahead in performance. If Phenom is significantly faster than Conroe/Kentsfield, then it doesn't look like Penryn will be able to save Intel. We should know for sure which scenario will pan out in the not too distant future.

Source : http://www.dailytech.com/article.aspx?newsid=8585