There was a M5 something quake north of Virgin Islands followed by a major gang (flock?) of aftershocks. There have been swarms in the Virgin Islands and Puerto Rico area the last few months. Don't know if this means anything...or even if this is typical of other subduction zones: the USGS-NEIC page reports all quakes over M2.5 that are in the USA and not such small quakes elsewhere, so since this is the only page I check, don't know if this behavior is typical of other subduction zones.
Chris