Yes, it'll be behind cutting edge 2006 PCs, but that's not the point.
Will it though - intel will need to put on about a 30% speed increase in 1 year to beat that - they certainly didn't manage that sort of jump last year and their meant to be having a LOT of trouble even beating the 4Ghz barrier.
Of course a lot will depend on the graphics card but you can garuntee the architecture will be faster then a PC simply because it won't have to support 10 year old hardware!