Pixar makes bettter CGI than ILM, so that's a mild plus.
This doesn't get my hopes up about the OOT. Disney has a decent track record with re-releasing their live-action films, but nothing terribly outstanding.
Their animated films are a much worse story. Song of the South is a no-show. Deems Taylor's voice replaced in Fantasia. Degraining and screwed-up colours in the classics.
They DO love their preservation, though. I read that they backed up ALL of their old film elements...