It doesn't just happen in one drawing file or with one block, it happens across the board in our office, for all 8 drafties using 2008.
If I am in a drawing and I zoom extents, then open the block editor, then close it, it zooms to some crazy spot in the middle of nowhere.
I copy the text below from my command line, maybe it has something to do with the "Regenerating model" bit.
Command: be
BEDIT Regenerating model.
Regenerating model.
Command: *Cancel*
Command: *Cancel*
Command: _BCLOSE
Regenerating model.
Regenerating model.