Looking at the current and future direction of BetFair (and betting exchanges per se) one observes a highly liquid 'trading arena' not disimilar to equity/commodity markets.

Within this 'trading arena' an Australian National TAB hosting a WIN/PLACE betting exchange would enjoy a critical niche market advantage - a long established pari-mutuel exotic (derivative) marketplace.

A betting exchange boasting ready (instant) access to risk reducing derivative trades (bets) would surely become an imperative trading tool - and something BetFair will never possess.