dual core.
the wikipedia article on the i5's show that the mobile i5's are dual core while the desktop i5's are quad.
the wikipedia article on the i5's show that the mobile i5's are dual core while the desktop i5's are quad.
all the i5/i7 macbooks seem to be running on the Arrandale line, so that would make them all dual core.
it looks like the top i7 macbook is using the Intel Core i7-620M processor. the two i5 models are the Intel Core i5-520M (2.4GHz) and the Intel Core i5-540M (2.53GHz).