AMD is going to start selling 65nm processors next year. Great article here, gotta read the whole article. Man those are going to be fast in the future.
I think it could go either way. When Intel started making their 90nm CPUs, it increased their speed a whole lot (Presc'hot'). When chips get made using a smaller manufacturing technology, the manufacturers are faced with problems of voltage leaks. Voltage leaks translate into more power being wasted on heat.
If AMD does it right, and gets 65nm to have low voltage leaks, etc, then the chip would be ok for OCing. But a chip that runs hot 'right out of the box' wouldnt be very good for OCing.
Intel also has 65nm wafers in the works so it can go either way at this point and time. AMD is indeed striving for thermal improvements with the next mobile platform using a decreased pin socket size and supposed >7w cores.