TechPowerUp found details about ASRock's upcoming 890FX Deluxe5 AM3+ motherboard. This new product will offer the AMD 890FX + SB850 chipset and will accommodate AM3+ processors as they come. More info over here.
The CPU socket is compatible with existing socket AM3 Phenom II and Athlon II processors, and future Fusion Black processors. This isn't particularly an advantage, because every AM3+ motherboard in the future based on 990FX will retain support for AM3 processors. On the other hand, 990FX motherboards could also embrace UEFI, something this board seems to lack prima facie.
Expansion includes three PCI-Express 2.0 x16, and two each of PCI-E x1 and legacy PCI. Storage is care of six SATA 6 Gb/s ports from the southbridge, two SATA unknown ports and an IDE connector from a third-party controller. Connectivity includes 8-channel HD audio with optical and coaxial SPDIF connectivity, six USB 3.0 ports (two by header), a number of USB 2.0 ports, gigabit Ethernet, eSATA, and FireWire.