I grew up on adventure games like this. Making them semi-multiplayer is a really cool idea. It reminded me of an adventure game MMO that's been in development forever (http://www.blackmasquegames.info/).

I didn't just grow up with adventure games like this, I grew up with these specific adventure games.

It looks like they actually implemented the old Sierra game interpreter in Flash. I recall there being an open-source clone of the interpreter under the same name, actually.

Activision Blizzard owns the IP for these old Sierra games. I wonder what with Lucasarts recognizing the value in their back catalog (e.g. releasing some of their classic games to Steam, remaking Monkey Island, and porting the latter to the iPhone) if Activision won't actually re-release or even remake some of these titles to modern standards.

I don't think Flash is used at all. It's all done with Javascript and HTML. They claim the games work on the iPhone as well.