By Nick Assinder
Political Correspondent, BBC News website
The Chinese famously cursed people with the hope they would live in "interesting times".
For Britain's three big party leaders (plus one), 2006 will without doubt be interesting. And, as far as politics is concerned, it will be all about them.
What lies in store for Blair in 2006?
Tony Blair's every twitch, utterance and policy move will be interpreted through the prism of his looming retirement.
David Cameron's early promise will be tested time and again as his opponents attempt to pitch him into the same retirement home occupied by his four predecessors.
And Charles Kennedy, who has been placed on probation by his own MPs, has just a few short months to see off his internal critics before they dump him.
Oh, and as far as the plus one is concerned, Gordon Brown's intentions will continue to fascinate and possibly even frustrate.
So, if nothing else, 2006 is likely to disprove the old claim that personality has nothing to do with politics.
And, it may be tempting fate, but it is quite possible that when the year ends it will no longer be Cameron, Blair and Kennedy facing each other across the floor of the Commons.
Just who it will be, and the twists and turns that will get us there, will lie at the heart of politics for the next 12 months or so.
Needless to say, however, there are a number of events already entered in the year's political diary which will help move the tectonic plates.
Schools bill will be big test
Almost as soon as MPs return from their Christmas break in January, the issue of education reforms will move to the top of the agenda.
Tony Blair is facing a huge backbench revolt over his proposed reforms with mounting concern over trust status for schools which, critics fear, could quickly lead to selection by academic ability.
Will the prime minister bend or will he push ahead secure in the knowledge he can win the day with Tory votes and, as a result, get at least one of his big "legacy reforms" on the statute books before he goes?
And how will Mr Cameron handle the affair? So far he has attempted to embarrass the prime minister and further isolate him from his backbenchers by offering him Tory support.
This issue will also provide one of the first platforms for Mr Kennedy to show that he has upped his game, as promised, and is able to exploit any divisions on the Labour benches.
Perhaps an even more difficult time for Mr Blair will come in the following weeks when his plans to reform incapacity benefit, by slashing the numbers eligible to claim, will be put before MPs.
This sort of radical reform of the social security system has landed the prime minister in serious trouble in the past with demonstrations outside Downing Street - presumably now illegal - and large backbench revolts.
Once again, how Mr Cameron and Mr Kennedy react to these proposals once they have been clarified by ministers could prove pivotal.
Kennedy has been placed on probation
Needless to say, a Commons defeat on either of these big policies would almost certainly mark the end of Tony Blair's premiership.
In April, Gordon Brown will deliver what is widely expected to be his most difficult, and possibly even his last ever budget statement before he takes over from Tony Blair.
After his "readjustment" of previous economic forecasts and predictions he will be forced to raise taxes, cut spending or increase borrowing, this may present the first real challenge to his reputation and leadership hopes.
And then there are the local council elections in May - always a rollercoaster ride for governments as voters traditionally use the polls to give them a good "kicking" as John Prescott once confirmed.
This time around there are polls in all London boroughs and 144 English councils.
Labour can expect losses, but the size of them could prove decisive in any moves to replace Mr Blair sooner rather than later - as many Labour MPs clearly hope to do.
But they will also prove a big test for Mr Kennedy, who will need to show his Liberal Democrats are not losing ground to a resurgent Tory party, while David Cameron, of course, wants to see exactly the opposite.
Cameron is seen as Tory hope
So, if there is one obvious date which could finally set the seal on the three leaders' futures, then it is 4 May 2006 - exactly one day short of a year after Tony Blair won that third historic general election victory.
Meanwhile, the issue of the withdrawal of British troops from Iraq and the developments in that country, will continue to have a direct impact on domestic politics.
Many now believe that by the summer recess, the tectonic plates will have moved decisively.
Mr Cameron will have either secured his position as the Tories greatest hope for a decade, besting Tony Blair and even hastening his demise, or failed to live up to his promise.
The Liberal Democrat leader may well have been replaced, one way or another, and possibly even irrespective of whether he has succeeded in upping his game.
And, perhaps most crucially of all, Mr Blair may finally be close to the end of his premiership.
Many Labour MPs now expect the 2006 party conference in Manchester in September to be Mr Blair's last. These MPs believe the uncertainty over the timetable for his departure is getting in the way of proper government, and they want clarity.
But does Gordon Brown - assuming he is still seen as the obvious replacement - want to take over that far away from a general election?
And even if he does, might there be a battle for the premiership rather than the orderly transition promised by Mr Blair?
An interesting year indeed.