Current 65nm Phenom's are already competitive with simmler clocked core 2's but they cannot reach high enough clocks to compete with intel's high end. That also shows in the overclocks of them being lower then intel too.
The new Deneb is going to be 45nm, so will take less power to run faster, and will have more room for cache on the chip itself. This will mean better clock rates, and an overall speed boost. It should easy compete with the current core 2's, and if price is right eat away at intels market share. People seem to be crying out for good AMD chips to upgrade to, so unless the chip is a techno flop it looks good for AMD.