I looked at their news and forums sections recently.The latest update for both were about a month ago.Is Tamriel Rebuilt dead?

Not at all. Check their forum thread http://www.gamesas.com/index.php?/topic/1178350-wip-tamriel-rebuilt-sacred-east/. They've been posting a lot of new screenshots of the new regions, and are relatively close to finishing the new map 3 and an updated version of map 2. http://www.gamesas.com/index.php?/topic/1178350-wip-tamriel-rebuilt-sacred-east/page__view__findpost__p__17562936

The project started just before Morrowind's release and is still going.. I wouldn't worry if they don't update their site for one month.