NOAA announced that the solar X-Ray Flux exceeded M5, 2013 May 03 1729 UTC (2:29 pm ET). Here's a view of the peak brightness of the flare from the EVE SAM camera. SAM is pinhole camera that is sensitive to X-rays. The X marks where the flare overwhelmed the CCD.
Another view showing the flaring region in the upper left limb of an AIA 94 image. The active region that flared has not yet been assigned a number, but keep an eye on it as it rotates into view!