The Fed has been very clear:

"In determining whether it will be appropriate to raise the target range at its next meeting, the Committee will assess progress--both realized and expected--toward its objectives of maximum employment and 2 percent inflation. This assessment will take into account a wide range of information, including measures of labor market conditions, indicators of inflation pressures and inflation expectations, and readings on financial and international developments. The Committee anticipates that it will be appropriate to raise the target range for the federal funds rate when it has seen some further improvement in the labor market and is reasonably confident that inflation will move back to its 2 percent objective over the medium term."

However, there is a huge disconnect between what the Fed is saying and what is being heard by market participants and the financial press (which has a overplayed the issue of timing).

Yes, it's a judgement call and Fed officials will differ in their assessments. It's also clear that 1) an initial rate hike is coming and 2) the pace of tightening after the first move is likely to be very gradual. We know that the FOMC was close to raising rates in September. Yellen and FIscher are on board for a rate hike by the end of the year. Global financial conditions have stabilized. The U.S. economic data, while softer, haven't been terrible (consistent with moderate growth). The wording of the October policy statement was clearly hawkish. The FOMC is on track to tighten in December. It's up to either the economic data or financial conditions to push it off that path.

We've also seen this play before with the taper tantrum. Adverse global market reactions did delay the tapering, but the Fed did eventually taper.