What's interesting to note about the 970 is that it's a cut-down high-clock version of the POWER4 series of CPUs, which has already proven itself in battle over a number of years. Both the 64 bit X86 alternatives have so far failed to reach the market (unless you count 900MHz Itanium 2 chips for $2700 as reaching the market).
However, prediction is never accurate, even more so when it comes to predicting the future ;-)
So for now we must continue to take anything that's presented as "fact" with a grain of salt. If the 970 can indeed hit the market in reasonable clock ranges at a reasonable price it will most probably be something of a success. But how much really depends on how Intel/AMD go from here. Do they continue to produce faster and faster 32 bit chips, or start migrating people over to 64 bit? Impossible to say. But I really expect Intel to reach something of an upper limit in clock frequencies soon.
Edit: I would just like to comment that I'm not saying POWER4 ain't been as expensive as Itanium 1 and 2. I meant to make the point that the 970 is a more marketable version of a battle-proofed chip, whereas Itanium 2 is still only for HIGH END :-)
