LucasArts: Amazing news coming Monday! Super excited! You have no idea how tough it is not to start yelling about it! But it's secret! Until Monday!
This has lead to a flurry of fan speculation directed towards the Twitter account, but the author is remaining tight-lipped, but has indicated that the announcement is "...awesome news for our old school fans."
Since the news is from LucasArts, speculation is immediately going towards a new Star Wars game, but outside a new entry in the X-Wing or TIE Fighter combat flight sims, there isn't much else "old school" content left in the galaxy far, far away.
The recent fervor over the return of the Monkey Island and LucasArt's re-release of Indiana Jones and the Fate of Atlantis as a bonus in the Wii version of Staff of Kings may indicate the return of one of the company's adventure games. Perhaps a revival of the long-cancelled Full Throttle sequel or another Maniac Mansion?