Unless it's somewhere I don't see, there's no way to set GCII plus all the expansions to download and install in one shot.  Trying to install DA gets you a message about installing GCII first, TA about installing DA first.  It's not a big deal, but it would be nice to have again.

While I'm thinking of it, is there any way to do global updates on all purchased software as well?

My apologies if these features are already in and I just overlooked them.  Other than those things, so far so good with Impulse.  Installation, updating and uninstalling all seem to be faster, though thats just subjective observation.  The new GUI is great too.

Vista Home Premium 64 SP1
Impulse  1.01.155