Although the HD 6450 has been previewed yesterday, you might have noticed that all of these cards came directly from AMD and current rumours put the card in retail on April 19th, or in just under two weeks time. The Caicos based cards were scheduled to launch next week, but have been delayed for some reason to April 19th. The lineup is pretty identical to the OEM one so you can expect HD 6450 based Caicos and HD 6570/6670 based on Turks GPU.
The HD 6450 was already detailed and previewed and you can expect a wide variety of these cards including ones with a low profile passive cooling and various specs. We don't know the precise reason for the delay but we guess that AMD and its partners simply wanted to sync the launch of both GPUs. Of course, the date isn't carved in stone but for now the 19th of April sounds like a pretty solid info.
The Turks still haven't showed up but our current info place them on the same date as the HD 6450. Unlike Caicos, Turks is scheduled to launch in two versions, as the HD 6570, or Turks Pro, and the HD 6670, or Turks XT. The rumoured specs are pretty much in line with the OEM specs, so you can expect them both to pack 480 SPs and a 128-bit memory interface but at a different clocks for both the GPU and memory. The HD 6570 should also feature GDDR3 memory, while the faster HD 6670 will end up with the GDDR5 memory. We are quite sure that we'll see a wide variety of cards as of April 19th with different coolers, PCBs, and clocks.
The HD 6450 has an expected sub-$50 price tag and might be good for low end HTPC of SFF systems. The details regarding the Turks pricing is still blurry but we guess that more info should surface pretty soon.