Cricket Australia (CA) confirmed it had given in-principle agreement to the International Cricket Council idea, which would pit the world's best team against a Rest Of The World XI.
They would play one Test and three One-dayers in September next year, probably in South Africa.
While Ponting and Ganguly welcomed the concept, they pointed to concerns in the game about an overload in international cricket schedules.
Australia, most likely the number one team, will have an Ashes series next year in England before the proposed tournament.
"I think it (the international schedule) is pretty full, yeah," Ponting said on Thursday.
"I think you only have to look at this year's program, next year's program to understand that there's not much room for too much more cricket in there. I suppose it is a little bit of a concern for the player group, that's it's going to be an extra Test and an extra three One-dayers but it will just depend how we're feeling at the time, even if it is us."
Ganguly echoed Ponting's concerns, saying: "Today they're always travelling at some stage, so a series would mean another few more days of cricket. That's the decision which needs to be made and which needs to be sorted out if that tournament's going to go on."
A CA spokesman said CA would consult with the players' body, the Australian Cricketers' Association (ACA).
ACA chief executive Tim May was unavailable for comment on Thursday.
"There are quite a lot of practical issues which have to be worked through, hopefully they can be," the spokesman said.
But Ponting and Ganguly agreed the series would be worthwhile if the timing issue could be resolved.
Ponting would welcome the chance to play against a side featuring stars such as India's Sachin Tendulkar and West Indian Brian Lara.
"Those sort of opportunities don't come around very often and it would be a great thrill to play against those guys but once again, it's a long way away yet," Ponting said.
"It's over 12 months away and we've got to focus on the things at hand here."
The ICC holds its next meeting in New Zealand next month when the plans could be finalised.
It was not immediately clear how the ICC would pick its World XI, with options being an international selection panel or using player rankings as a guide.
Using the current PricewaterhouseCoopers rankings the team would be: Herschelle Gibbs (RSA), Mark Richardson (NZL), Rahul Dravid (IND), Brian Lara (WIS), Inzamam ul-Haq (PAK), Jacques Kallis (RSA), Sachin Tendulkar (IND), Muttiah Muralitharan (SRI), Shoaib Akhtar (PAK), Shaun Pollock (RSA) and Makhaya Ntini (RSA).
ICC gives green signal to 'Best vs The Rest'