There will probably be the beginnings of a double dip recession in the UK and the whole of Europe due to 1920s / early 30s style austerity programmes. Growing demonstrations and possibly even riots will take place against the cuts. As unemployment and poverty rise, support for right-wing extremist parties such as the British National Party will increase across Europe, though there will be some revival in the poll ratings of the radical and moderate left and Greens too. Support for pro-austerity conservatives like Cameron in the UK, Merkel in Germany and Sarkozy in France will erode further as cuts start to bite and they're squeezed between the left and centre left on the one hand and the far right on the other.
The SNP will no longer be the largest minority party in the Scottish parliament after the 2011 elections - Labour will be, due to the recession and the SNP being seen as the incumbents in Scotland (plus much misleading Labour, Conservative and media propaganda about Megrahi, who is almost certainly not the Lockerbie bomber and never had a fair trial).
Lib Dems will lose most of their Scottish parliament and council seats. As a result Labour, while taking some seats from the SNP and Lib Dems, will be unable to re-form its past coalition with the Lib Dems - and will be forced to rely on the Greens the way the SNP currently do.
The Greens will have picked up a couple of seats from the Lib Dem collapse on the second vote and from the ongoing civil war between the SSP and Solidarity (unless that’s been patched up by May, which seems unlikely) and will have more influence than they do now.
Labour will win the Oldham by-election with a greatly increased majority, with Lib Dem votes slipping away to Labour and the Conservatives.
Republican control of congress will make it impossible for Obama to get any further meaningful continued welfare support for the unemployed or economic stimulus through congress and put more pressure on him to be more nationalistic and belligerent in foreign policy.
The growing extremism of the Israeli government will make another Gaza style war likely - and wars with Lebanon, Syria or even Iran a high risk.
If the double dip recession spreads globally (with about the only thing currently militating against it being Chinese economic stimulus programmes and increased minimum wages) World War Three over disputes between the allies of the US on the one hand and China and Russia on the other becomes a bigger risk (e.g Georgia, the two Koreas, Pakistan vs India).
War between India and Pakistan over Kashmir or continued Pak military support for terrorist groups in Kashmir and India is also a serious risk.
NATO forces will begin a withdrawal from Afghanistan and an attempt to get a coalition government there, as they have no way to defeat the Taliban while our Pakistani military and Saudi "allies" continue to arm them, partly with arms and funds our own governments have given them - and cannot target the Pakistani military as they require its co-operation to get enough supplies through the ports and passes of Pakistan into Afghanistan.
This will not stop the US or its NATO allies continuing to sell arms and provide military aid to these supposed "allies" as a means of making profits for their own arms and oil firms.
Jihadist terrorist attacks worldwide will continue to grow due largely to the continued US and European policy of backing the Israeli occupation of the West Bank and the Blockade in Gaza, their support for dictatorships in Jordan, Saudi, Yemen and Egypt - and US cruise missile attacks and US and British special forces operations in Yemen, Somalia, Pakistan and Afghanistan.