According to GW, Warhammer Armies Dwarfs will be released shortly before Christmas (in the UK, at any rate). It contains all you'd expect and more, with Rangers (new infantry type), improved Miners, new rules for the Anvil of Doom, Dwarf runes, and new special characters Runelord Thorek Ironbrow and Dwarf King Alrik Ranulfsson, background and stories. More information will be available in White Dwarf 253, which comes out in mid December.
If you went to Games Day, and looked at the massive Dragonslayer display diorama, you might have noticed two new Felix & Gotrek models, designed by Alex Hedstrom. It is strongly rumoured that these models will be going on sale at about the same time as Warhammer Armies: Dwarfs, exclusively from the internet.