For me the single nicest thing in the IDM 4 release is that now if you
link ECMA functions to a driver (You had to do this, so they would be
available to use in Policy preceeded by the es: namespace) you can use
them in Workflow. (Obviously in that case, you link them to the User
App driver).

Same for GCV's!

This is amazingly useful!

There are now functions to use GCV's in Workflow, and to use existing
ECMA libraries you built in Policy.

While GCV's appeal to me more, (since I HATE hardcoding paths, URL's,
username's in a workflow) in reality having a script library available
will be more useful.

I was reviewing some workflows my boss had done, and virtually every
instance of ECMA was something like:

function foo(x,y) {
whatever;
}

foo(x,y);

In other words he kept having to define the function to then call it.
INstead now he could define it once and reuse it as needed!

Yay!