So, week ago we seen Kaveri and this is exactly four times more cores on the chip:
Source: http://support.amd.com/TechDocs/47414_15h_sw_opt_guide.pdf (Figure 14, page 197)
Newer models of Family 15h processors offer five links for connections to I/O and other processors. Of the five links, one link suports PCIe 3.0, two support coherent Hypertransport, and two are capable of either coherent Hypertransport or PCIe 3.0. These processors have 8 compute units (16 cores).
What does that mean? Well, probably some server based CPUs or CPUs for people that need lots of processes? Could be (with the Mantle scaling almost perfectly with more cores) also interesting for gamers, as the power will be significant.
Never the less, the mystery about four memory controller channels, with only two being active on Kaveri, is starting to make more sense. No-one in the right mind would expect that 16 cores could get along with memory access with only two channels. Especially considering that the space for L3 cache is limited - cache eat most of the die size, so roughly when we know, that four Streamroller cores with L2 cache eat abou 62mm square of die size, then 16 cores are somewhere around 245-260mm die size. Of course we have to add memory controler, northbridge, and PCIE lines… so we are getting something around 300mm die size, witch is not uncommon to be realized under 125W TDP.
However with 16MB L3 we getting to about 360mm and with 32MB we getting 430mm die size need, witch is somewhat extreme and over the line.
On the other hand, 16MB L3 is not that much for 16 cores. So it all depends on how adventurous AMD will be. Sometimes they cross the limits (eg. the 5GHz CPU with overhelming TDP even for most watercooling solutions, lol).