At 02:55 UTC today (18.12.2012) there was a magnitude 3.3 earthquake in Bárðarbunga volcano system. Earthquakes are common in this area so this activity is no surprise. Origins of this earthquakes are due to tectonic movements in the area. Not magma related changes.
Aftershocks have followed this earthquake. So far the largest one got the magnitude 2.2. More earthquake activity can be expected in this area. But that is normal and not unexpected.