They need to clock well this is the factor for me, c2d/quad clock so good why would anyone bother if they can get the same performance for a smaller price.
phenom's already do 3Ghz easy, quite a few do 3.5Ghz, most fall inbetween which frankly on air is roughly what you'd of gotten out of a Q6600. Again for 99% of users you can't, no matter what a benchmark tells you, feel the difference in games, watching video, surfing the net, etc, etc, etc.
So far it looks like they'll be roughly 20-30% faster than a Barcelona clock for clock but the fact is AMD want to win back the appearance of being budget and more affordable. But it doesn't really matter, they sell loads but can't really make an impact on the market till the new fabs are up and running, which aren't "that" far off and have more than ample funding so they are certainly being built.
But in the meantime they now have more than ample cash to keep them going and let them persue long term goals rather than short term.
Short term, the Barcelona was cut down from what it needed to be as they have limited funds, limited production capacity and simply put they had to make Barcelona perform well but be as small as humanly possible, they did a truly, absolutely outstanding job, i mean, insanely great job. THe problem is people see the chip as trying to be the best it could ever have possibly been, and seeing as the ATh 64 was faster than a P4, this should have been faster than a C2D chip, which was and is ridiculous.
INtel are essentially producing chips with almost zero limits to its design or production so it could do exactly what it wants with really no sacrifice at all.
AMD have to cope with increasing demand and only two fabs, jump from dual to quad core, their only goals were, largest possible number of chips and be remotely fast, they did great.
With massive limits in place they made a chip that on any home computer is cheaper and produces the same performance for most home tasks including gaming. On the server side the great scaling of the 4/8 way combo's still made it "ok" even when it lacked raw power.
Shanghai/Deneb is essentially the "we might be limited but we've got trillionaires backing us, screw size, screw loss of sales and screw everything , make the chip what it wants to be and in a couple years we'll have fabs to cope with it properly" , so Barca mark 2, (or the original barca) comes out with the cache it needs, the space for more core logic and you have a better chip which should clock better and performs a lot faster.
It will kill the server market as its already faster than the C2D based Xeon's, and Nehalem 8 ways aren't out for a year.
It thing that will be really interesting is when both companies have multiple fabs, AMD have the money to design the chips they really want with the same freedom Intel do. At the moment AMD are in a boxing fight with a hand tied behind their back. In a couple years we should get some silly chips for silly cheap.