Beautiful imagery - but still fails to address the key problem: timeliness. I assume at least some of the satellites in use were in polar orbits, so there's a variable delay before the patch of atmosphere you want gets imaged. Geostationary sats are (maybe...) too far out to deliver the detail needed and anyway don't carry the relevant sensors. (I may be entirely wrong on this.)
Geosats are very capable of delivering ash cloud information...but the problem for places like iceland is that the spatial resolution is quite poor (due to the angle between iceland and the equator):
EUMETSAT IPPS animation - Meteosat 0 degree Ash Iceland
Our geo satellites contain all the sensors needed for ash analysis. Although, as always, additional sensors would be an improvement (which will arrive in 2015).
On the plus side, because iceland is near the poles we gain a lot of high resolution polar data at high frequency - we can gain 5-6 images of iceland per day from polar sensors.
(edit) Oh, just noticed that the post was a month old. Apologies.