Reminds me of the "Digital Zoom" race in the camcorder market. Pointless apart from some very specialised applications (El Reg audience only, not Joe Public or MS Office business user).
New machines are getting shipped with 64 bit Vista - but there is still a lack of software to make use of this - MS Office 2007, Open Office, Adobe Photoshop and Premier 7 Elements... mostly all software is 32 bit - again apart from specialist applications (i.e. expensive specialist professional software). How many mainstream applications are engineered to make maximum use of 4 cores with hyperthreading ?
Software seems to be lagging behind hardware at the moment.