A girl I know wrote gullible on the ceiling of her school. She kept telling people that the word was written on the ceiling - Charlie Demerjian
It's socket compatible, so you will be able to plug it into the same sort of place, but you won't be able to make it work. It seems that the CPU has turned out to be somewhat incompatible with existing 915 and 925 socket 775 motherboards.
The motherboard manufacturers will have to redesign the motherboard in order to make dual core 8xx CPUs work in existing motherboards but it's unlikely that anyone will do such a thing.
Early adopters of socket 775 will have to buy a new motherboard based on the 945 or 955 chipset in order to make their new dual core CPU work.
Many won't be happy to replace their motherboards just months after they bought them but they really don't have any other choice. ยต