I've been trying to read what's happening, and where the evacuations are. But, on US sites, Britney's latest drug and family issues are way more important.
Here's what El Comercio (the main Quito newspaper) says. And here's an interview with more information.
It looks like Banos (with a tilde, however one does that on a computer) hasn't been evacuated (since you can find pics of people praying there; it's a big pilgrimage site for miracles).
What's this, you wonder? Tungurahua is one of the great volcanos in the central Andes of Ecuador, and it's erupting. The city of Banos is a few kilometers towards the north, on the road down into the upper Amazon basin. Ambato is a bit further north, 30 kilometers, perhaps?
Here's a satellite image: WAY COOL! Though it doesn't show the volcano erupting.
If I were a praying person, I'd be praying now. Keep Ecuador in your thoughts. Here's the website for the Cruz Roja Ecuatoriana, which has more information about the emergency.