Unfortunately, the third piece of news you heard is correct: Motorola has decided not to release the MPx220 (or the MPx) locally.
A Motorola representative told CNET.com.au that due to the strong focus on 3G in Australia this year, with Optus, Telstra and Vodafone launching third-generation networks soon, Motorola has decided to focus on its 3G handset range. Currently, the only 3G operator is Hutchison's 3, on which the Motorola A1000, E1000 and C975 are available.
However, the MPx and MPx220 are being rolled out in a number of countries in the Asia Pacific region that do not yet have a 3G network up and running.
Update: 31 March, 2005
Motorola has changed its mind again and has decided to go ahead and release the MPx220 in Australia. A Motorola representative confirmed it is currently scheduled for release in June 2005.