First off, nice model you got there!
Now, few basics about topology:
- triangles are bad because they cause artifacts with smoothing, subsurf or multires. They break edgeloops and behave weird in animation
- poles (=vertex with 5 or more edges) must be used carefully. They can create smoothing artifacts, too. And they also break/redirect edgeloops. If you know how to use poles correctly, you can improve your edgeflow in some points
What's "edgeflow"? It defines where you can add edgeloops or slide edges. A good edgeflow allows you to add edgeloops in a way that follows the natural shape of a model.
It's a bit hard to describe but I'm sure this happened to you before: You want to add an edgeloop and can't slide the loop after adding it. So you have to do it by hand => bad edgeflow!
You want to sharpen an edge by adding an edgeloop but the loop curves away from the edge halfway => bad edgeflow!
For real good information on edgeflow/topology, look here
Another quite huge resource can be found here
I can't tell you by looks if your model has a good topology or not. You can test that by adding subsurf or by adding in edgeloops.
Sorry, I got now topology tuts on wolves but humans/characters:youtube edgeflow tut1
, youtube edgeflow tut2
There are some pretty good topology tuts at Blendercookie, too:male and female torso
, controlling the edgeflow
And, last but not least, there's always Gollum:
Hope this helps to some extent.