You really think things will go up after the movie (I don't)?
But it would be nice to make a huge profit on my MIB G1 Optimus Prime.
Based on all the positive buzz from the movie sites, and non-Transfans talking about the movie three months out, I think it's likely to add value to any of the G1 figures/ Reissues in good shape.
I mean, it might do to TF values what Phantom Menace did to vintage SW value, but as long as the movie is marginally good, there will be noticeable price increases in the older stuff. Beast Wars and any of the AEC figures not directly related to G1 homages, on the other hand, should be easier to get. That's my guess, anyway.