Are triangles ever a good thing, or should i always seek to eliminate them in other apps ?
No triangles = no problems … well that is unless you come up with n-gons 
Whenever you subdivde a mesh, no matter in what application, triangles will give you problems. What you can do of course is trying to put them in areas of your mesh, where you won’t see them.
Hope that helps.
thank you.
I will be the arch triangle killer from now on
how about some feed back on the “changeling”
ie: the quad that looks like a triangle
Well a good geometry or topology does not only mean, that you should avoid triangles, it also means that, as a general rule, you should keep your quads as evenly square sized as possible.
Obviously this is especially true once you get into animating.
As for myself, even if i know that the model will never be animated i am trying to have the cleanest topology possible. Just in case you know
lol triangles turn into 4 sided polys anyway in zb.
I use triangles to keep details in areas that really need the polys. If you were to flow all your edge loops perfectly you end up just wasting polys.
Just dont use too many triangles. Be smart with where you use them.
As soon as 64bit hits i would no longer need to use triangles, since i wouldn’t have to worry about wasting poly-count so much.