After the GTX 660 is launhced, there will be another card introduced. roughly a month later (as it seems) the GeForce GTX 650 should arrive September 17th.
The sub-$200 card is based on the 28nm GK107 GPU and would offer 384 shader processor cores alongside a 128-bit memory bus and 1GB GDDR5 memory. And that's as short this news item really is, as we don't have anything else or new to report on the product:)