Looks like Gigiabyte is the first to release an AM3+ board:
It will support the new 32nm AM3+ CPU's and the entire AM3 lineup.
Newegg already has it available for retail sale.
The ASUS Crosshair IV Formula released a bios update to support the AM3+ CPU's.
Now if I can just get my hands on an AM3+ CPU, stay tuned...
Phenom II X6 1100T B.E.@ 4.26GHz
Corsair H70 Core Hydro
ASUS Crosshair V Formula
2x4GB G.Skill RipjawsX@ 1894MHz, 9-10-9-28
SLI: 2x EVGA GTX 570's@ 902/1804/2032
Creative SB X-Fi Xtreme Gamer
Corsair HX850W Modular
Cooler Master HAF 922
2x Win 7 Home Premium (x64)