Somehow I ended up (through a haze of late night blog click through's) at Scott Guthrie's blog in a his First Look at Orcas Presentation post.

"Orcas" has some new JavaScript intellisense capabilities to help you dev better, faster, cheaper - the March CTP was recently released (both installer and VPC)

Big Benefits:

- Intellisense in JavaScript

- Rich type inferencing (i.e. method returns a certain type therefore the variable being set carries that type and the goodness that goes with it.

- JavaScript debugging

Check out Scott's post here.