Found this little gem on YouTube:
Not a lot there, but thought it was some way cool footage of those two interacting on a movie set decades after Rocky IV.
Now, chances were pretty good I'd see this movie anyway -- I mean, how could it be bad with the aforementioned premise? But I also read an article recently (Maxim maybe? Probably ... I was on the can at the time...) where Stallone says there's an homage to Rocky, where he finds himself face to face with Lundgren during a scene, looks at him curiously and says something like: "Uh.. we've been here before.."
Sold! My ticket is as good as bought ...