SCE can't compete with the Wii on the basis of price, regardless of any price trimming/slashing. That's one area in which they will never be able to compete with Nintendo due the gap in manufacturing costs alone.
So in that respect, if a quick pick up experience is what consumers want, it's tough to beat the current $199 Wii bundle.
The only "casual" buyers I see for the $399 bundle are those who are more interested in an all inclusive package to go with their HDTV for media playback, video store and Blu-Ray movies.
Beyond that, it's really going to have to be on the merit of the games being released whether these bundles sell to new consumers rather than the "Wii HD by Sony" concept.
As for existing PS3 owners, a lot of it will depend upon the strength of backwards support (most FPS games would be revitalized by point aiming rather than analog stick aiming) as well as (once again) the strength of the initial selection of games and future offerings.
Weak or lukewarm support (like the PSEye) will result in a lot of current owners passing on Move, or buying it early and not using it later when future games fail to deliver.
