If I cash in all my stocks today due to F.C. uncertainty, what are the + and - of doing this?
Obviously depends on tax bracket.
Makes sense to preserve losses until 2013 then sell
For LTCG/STCG's your FP entails selling in the short term, sell now.
For securities you were planning to hold longer term, hold them.
(if you sell then buy back, you accrue further gains based on holdings less 2012 tax exposure. i.e., you profit more simply maintaining the investment despite a less favorable 2013 tax environment)