There are some great Brazilian Churrasco houses open on Darling Harbour - and the second one seems to have opened just in time for this World Cup in Brazil! They are just past the IMAX theatre and across from the convention centre area. I'd bet money my fiancÚ and I head there at least once to soak up the atmosphere. It's a real shame that they aren't having the FIFA sponsored area set up anywhere this year - that was great four years ago (maybe there will be something public in Martin Place?). The Golden Sheaf in Edgecliff is a really nice, large and comfy pub/bistro with great food, otherwise Martinplace Bar in the city or somewhere like that - if no one is organising a World Cup party that you know :)
I will be heading up to Norton Street for an Italian game, and to The Star to check out the events room they have set up (not sure which game this will be best for, however) Bittan in Erskinville are doing some of the games (brunch time ones) so might head there for a French one, if I can swing it.