Wow Thats a Big move. Lets hope it just makes things better for us :
More here :http://www.theinquirer.net/default.aspx?article=35818
THE ATI R600 will represent the last of it's breed, the monolithic GPU.
It will be replaced by a cluster of smaller GPUs with the R700 generation. This is the biggest change in the paradigm since 3Dfx came out with SLI, oh so many years ago.
Basically, if you look at the architecture of any modern GPU, R5xx/6xx or G80, it comprises pretty modular units connected by a big interconnect. Imagine if the interconnect was more distributed like say an Opteron and HT, you could have four small chips instead of one big one.
This would have massive advantages on design time, you need to make a chip of quarter the size or less, and just place many of them on the PCB. If you want a low-end board, use one, mid-range use four, pimped out edition, 16. You get the idea, Lego.