Scott,

Digging in is not a sign of strength. It is a sign of weakness. My guess is that the Russians can’t supply enough fuel to keep its vehicles mobile. At the very least in mobile warfare you park your vehicles and are prepared to roll at a moments notice.

There is also a report of Russians burning one of their own APCs which broke down.

All signs of forces long in tooth short in tail. i.e. just the way it has been for 70 years.

Is it possible the Americans will wind up with a Black Sea port?

I have a few more words along these lines at:

Russians In Georgia Demobilize.