According to HKEPC, AMD plans to release the 3.2 GHz Phenom II X4 955 in April while the 3.1 GHz Phenom II X4 950 will not even make it to the market.
Chinese website HKEPC said that sources in the Taiwan motherboard industry claim that the 3.1 GHz Phenom II X4 950 will not make it to the market, but will be replaced by the 3.2GHz Phenom II X4 955 in April thanks to better-than-expected yields of the 45nm Deneb quad core processor. Built for the AM3 socket, the processor will have the same 8MB cache and 125W power envelope as the previous 950 processor, but will be 200 MHz faster than the current top-of-the-line Phenom II offering and support DDR3-1333 memory.
In addition to the 3.2 GHz Phenom II X4 955, there's talk that AMD plans to launch the Phenom II X2 500 dual-core line, originally codenamed as Callisto, listed for a release in mid-May. The Phenom II X2 550 will clock in at 3.1 GHz and feature 7 MB total cache, whereas the Phenom II X2 545 will clock in at 3.0 GHz and feature 7 MB total cache as well. Supposedly, the Callisto processor is just the Deneb with two cores disabled; each chip uses 6 MB of shared L3 cache and 512KB of L2 cache per core.
Finally, HKEPC also mentions the Regor, a low-end dual-core Athlon X2 200 which apparently doesn't feature L3 cache like the Callisto, and only has a 65w power envelope compared to the Callisto's 85w power envelope. Although built for Socket AM3, the Regor provides 2 x 1 MB of L2 cache only.
Although AMD plans to release the X4 955, X2 550 and X2 545 during April and May, currently there's no word on the actual cost of each. Stay tuned as AMD officially reveals the processors (hopefully) soon.