I recently went through a realm connection myself and it completed without a hiccup. The problems some players on US realms Nesingway and Vek'nilash have experienced seem to be isolated incidents.
View the full list of realms after the break. Keep in mind there is currently no ETA for these connections.
- Burning Steppes and Kor'gall
- Mug'thol and Dethecus/Theradras
- Temple Noir and Naxxramas
- Crushridge and Emeriss/Hakkar
- Sporeggar and Scarshield Legion
- Vek'Lor and Arthas
- Shen'dralar and Zul'jin
- Haomarush and Dragonmaw
- Chromaggus and Shattered Halls
- Shattrath and Garrosh
- Valvengyr and Nazjatar
- Bladefist and Zenedar
- Runetotem and Killrogg