HD transmissions in Australia are 1080i 50Hz or 720P 50Hz, with SD at 576p 50Hz.
Film based stuff is *effectively* progressive here even in 1080i as each frame is just represented by the two fields, and they speed the 24fps film up to 25fps for PAL HD transmission.
In the US, 1080i is 60Hz, which means they still do the "bloody awful pulldown juddery interlaced abortion mess" [technical term] to make 24 go into 30.
They missed the chance to move everyone to 72Hz worldwide and bypass all of this crap.
Live transmissions like sports are true interlaced 1080i, by this I mean the two fields are not half of one progressive frame, so you can't convert it to progressive and retain the resolution.
Film based material in the USA is still stored on HD-DVD and Bluray discs as 24fps and the players turn it into the juddery mess that is 60Hz, exactly the same as DVD where if the material came from film it is nearly always stored as 24fps on the DVD.
The GOUT poses a problem though, if using the NTSC LD pressing master as their source, then it will be BAPJIAM encoded already, so they need to either do an IVTC of it before putting it to DVD or (heaven forbid) just do a straight transfer as if it was an interlaced video source and waste a ton of DVD space encoding the mixed up frames.
The PAL versions should be straight 25fps (effectively progressive) either way.