Cricket Australia are concerned about attendance this season with crowd numbers being at 20 year lows. To add insult to injury this year the world cup is in Australia/New Zealand.
I think the problem is lack of stars. We aren't clobbering the world like we used to 5 years ago and nobody is regularly performing miracles. I think Mitchell Johnson qualifies as a bowling star but there's no batter that is regularly stepping up.
South Africa are ranked number 2 in the world and Australia are number 3. India are number 1. So theoretically this is just about as good as one day cricket gets.
The other theory that I have is that it's not a tri-series (three teams).