I suppose it depends if you believe (or not) that QE has kick started the US economy (all the stats are promising but the fiscal cliff still looms), that China and Asia is back on track (again the stats are promising), that Europe isn't going to implode (jury's out but it is certainly more promising) and that emerging markets aren't going to continue to emerge (just look at some of the growth stats out of Africa for example).
After the credit crunch, euro crisis, fiscal cliff and 2012 predicted end of the World (the Myans were about as good as Gordon Brown on boom and bust) I think people and businesses just want to get on with things and start reinvesting and growing.
Looking at the FTSE 100 7,000 seems possible, corporate earnings remain strong and UK markets were undervalued particularly given their international earnings. A key component, the banks, currently make up 15% of overall market cap and they have been at rock bottom values for 5 years so their continued growth should drag the FTSE upwards. On top of that the two major oil businesses make up around 14% of the FTSE and a gradual improvement in their fortunes should prime the pump a little more.
As for timings hindsight is a wonderful thing but foresight is so much more valuable. I wish upon wish I'd stuck another £50k into Lloyds at 24p but with investments in HSBC, Barclays, Investec and Standard Chartered I thought I was over exposed to the sector and could not override my contrarian tendencies. What a foolish Fool am I.