New 45nm based Wolfdale dual core is scheduled for second half of 2008 and it looks it will sit in-between E4700 and E4600.
The new CPU works at and will have 3MB cache which is it its strongest point. The new Dual core E7200 is Wolfdale, 45nm based but it will end up 70MHz slower than E4700 that currently works at 2.6GHz.
The new works at 2.53GHz but it has that might even make it faster than E4700 that works with FSB 800. It should be available in second half of 2008.