AMD certainly has some horses to race the Core 2 Quad marchitecture. We have already told you a lot about the Agena FX, the native quad core for gamers, and its 4x512 KB cache and shared 2 MB of cache.
Shangai will be manufactured in 45 nanometre and will hit the higher speeds. Despite more L3 cache memory the new CPU will have some minor architectural changes. It is a native quad core but you will be able to put two of them together for eight cores.
Internally AMD calls this project K10.5 and it indicates that we are not only talking about a shrunk chip, it has some new marchitecture inside.