We are no experts that is for sure. winoneforthegipper pointed out this one had a high chance of going off. We had a small disagreement on how big it would be.
If you are getting any ash get you and your friends some dust masks. You can breath in glass shards which i don't need to tell you how bad that can be.
New pictures, it seems the eruption crack is about a kilometer in lenght (click in military terms), and is on or next to the popular walking route over Fimmvörðuháls. Now I wish I had walked there.
Now there is pretty good change that this will be a small eruption that will not be to devastating, except maybe to the walk route mentioned previously. In fact, it could become a little bit of an attraction to come and see it, at it seems to be in a smaller scale than feared.
Strangely some panic came upon the international flight system that chanceled flights to and from Iceland and over the country. It sounds like they have never experienced a volcanic eruption before.