It's a possibly historic day, as the Fed may or may not take its first tentative steps towards scaling back on some of its post-crisis easing measures via "tapering" the pace of Quantitative Easing bond purchases.
A full preview of what's at stake, and what the Fed might do is here.
In the meantime, markets gained in Asia, but in Europe and the US things are basically flat, as everyone waits before the big moment, which doesn't come until 2 PM. Things are likely to be fairly quiet until then.