Amazon has a "email me when this becomes available" for anything out of print or not yet released. They have the same thing for the Holiday Special.

Honestly, I hope they take another 5 years on the blu-ray. It gives more time for the OOT dvd's including the new slim sets to sell. And it suggests that LFL actually might put some effort into their next release. With each year, I don't think Star Wars is as big as it once was. People will move onto other things. More people will look at online reviews and learn what the term "animorphic widescreen" is. So the longer they wait, I figure the more spectacular it will have to be to get people's attention, much less their money.