Details on Disney's upgrades to Space Mountain at the Magic Kingdom are beginning to leak.
According to construction notices filed by Disney which are believed to apply to Space Mountain, audio-visual upgrades and an "interactive queue" will be added - possibly a reference to easing guests' wait for the ride by adding interactive games into the queue system (as seen at Soarin' in Epcot). Disney has already confirmed that a new queue enclosure will be built for the ride.
In addition, Screamscape reports a rumor that plans to add an on-board audio system have been dropped. With Disney cutting costs across the board to cope with the recession, this rumour has some credibility. Disney has already confirmed that the coaster's track will be replaced, but that the layout will not change.
Space Mountain and the Tomorrowland Transit Authority both closed for refurbishment in April this year. Space Mountain is expected to reopen on November 25, with Tomorrowland Transit Authority set to be back in action by August 25.
You can keep up-to-date with the latest confirmed and rumored ride "rehab" periods using Theme Park Tourist's "Rehab Watch".