"Will they have to re-release movies in the new format?"
Studios will and right now there are two competing formats with studios lined up on both sides.
"Will everyone's present libraries of movies become obsolete?"
I believe there will be manufactures of DVD players that be backwards compatible. How that will mix in with the two competing HD DVD formats, I don't know.
For a great information site go to:
thedigitalbits.com
Since then, we have enjoyed the investment tremendously, and it cost less than a vacation than we might not have gotten anything out of...with netflix, there's always a movie night. And the bathrooms in the theatre are clean...
I don't care to buy movies because I don't like storing them. I can remember when the kids were small and I was snowed under with all those videos and boxes.