It’s extremely unlikely there will be no action on the fiscal cliff.
If nothing else, I do fully expect the Doc Fix and AMT patch to both be passed again with bipartisan support. Neither side wants the Bush Tax cuts to expire for the poor and middle class, but the Republican know they can’t let the Dems have those if they want to keep fighting for tax breaks for the rich.
There’s a ton up in the air right now simply because it’s inconceivable that no action will happen, but it’s also hugely questionable what action will happen. But for you richy rich pants out there, definitely be prepared for your capital gains rate to go up.