Yes! In the past few weeks the USA and China declaring they will work together to cut carbon pollution. And double yes! The EU has agreed to cut its emissions by 2030.
Both of these developments make the prospect of some kind of climate deal at the crucial Paris meeting of the United Nations Framework Convention on Climate Change (UNFCCC) in a year's time much more likely than it was only a few weeks ago.
But who will set the rules for the deal? Who will determine if it is adequate? And importantly, who will decide whether each country is taking on its fair share of keeping the world safe from devastating climate change - the fate scientists say awaits us if global warming rises above 2oC?
It is important that the current UNFCCC negotiations in Lima, Peru answer all these questions as fully as possible, forging the template for a new global deal by agreeing as far as possible what each country must declare in their commitments in a year's time at Paris negotiations.
The aim is to prevent what those of us close to the process call a 'Copenhagen moment'. Memories are still fresh of the manner in which a UNFCCC conference attended by heads of state in Denmark five years ago saw a near collapse of the entire climate negotiations process.
This time round the aim is to ensure that the international political negotiations happen well in advance, to enable Paris - where a deal is supposed to be agreed to come into force in 2020 - to pass off in a spirit of co-operation.
The augurs so far are hardly encouraging. The United Nations Environment Programme, which promotes sustainable development, predicts that if all the carbon cutting pledges so far made were implemented, we would still by 2020 be emitting 10 gigatonnes more carbon a year than the limit needed to stay on track to keep the temperature rise below 2oC.
Also this year the Intergovernmental Panel on Climate Change made very clear in its 5th Assessment report that there is no 'carbon space' for poor countries to grow into. In other words, their future development must be low-carbon - as indeed must be that of richer countries.
Wealthier countries must take increased action rapidly to cut emissions, but middle income and poorer countries too must be part of the solution. This will entail international support to help them develop their economies in a low-carbon way, enabling them to leapfrog the pollution path.
The big question for the present negotiations in Lima is what elements should countries declare in what gets called their 'nationally determined commitments'?
Most of the wealthy countries, including the USA and EU would prefer only a mitigation target to be included in their pre-Paris commitments. This means that while undertaking to restrict, if not completely exclude, new carbon emitting development, capping present emissions will be limited.
Developing countries, meanwhile, are insisting that they can only commit to low-carbon development and adaptation if provided with the means - including finance and technology - to deliver.
It is essential, therefore, that there is a match between
-what developed countries are offering, in terms of domestic emissions reduction plus a commitment to deliver finance and technology to poorer countries; and
-what developing countries are willing to offer, in terms of domestic emissions reductions, along with their declared needs for finance and technology to take a low-carbon and climate-smart development path
All countries need to express why they think their commitments represent their own fair share of the effort. The aim is not just to balance the figures, but to leverage trust between countries in the negotiations, and allow all parties to be willing to participate on fair and transparent terms.
So where do the middle income countries feature in this equation? Instead of just a rich country/poor country split, Brazil has suggested a middle tier for middle income countries.
Alternatively, there could be a spectrum of commitments depending on a countries responsibility for causing climate change in the first place, and its economic capacity to act.
Analysis by the US think tank EcoEquity and the Stockholm Environment Institute suggests that it is possible to calculate what level of action each country should be bringing to the table based on its previous record of pollution, and how much international support each developing country should receive to achieve low-carbon development if we are to stay below 2oC.
This analysis shows that a country such as India, for example, would become a net winner if it pushed harder for a fair deal in which it is supported away from fossil fuel dependency towards a modern clean energy system. But this will take political courage to acknowledge.
Overall the discussion has to move from defensive discussions of nations asking 'how little I can offer and still make it look like a deal' towards 'how can we work together to form a deal which will deliver a low-carbon future for the world which keeps us all safe'.