HP just released the source code for their Isis browser for webOS on GitHub and their comments about it all trumpet its use of Javascriptcore (and QtWebKit). They appear to be using code from around r104935 and it's likely they'll want to pull in the LLInt/three-tier VM.
It's newer than anything they've shipped (actually just about everything is, which is a nice change of pace) and we're all waiting like kids on a sugar buzz for the HP-supported effort by the homebrew community to get all the new pieces out through Preware. I will be amused if this hits webOS as an official release before any of the other tablet OSes, but HP seems to be taking the Dadaist approach to the platform.
