There is a way to just get back what you want. Go to Compressor, open Share Monitor from there.
In the dock you will see the Share Monitor.
Right Click it, and select: always show in Dock.
Voila.
It's still a stand alone application, but I think it's hidden somewhere in Application Support.
I *do* have noticed, that every time I start Compressor 4 now, it asks me to put sharing on (for my cluster with my multiple cores), and if I close it, it says it will stop the sharing. This stops me from stopping Compressor while doing an encode.
I used to just start the render in Compressor, and then close it, and just have the Batch Monitor open. Now I keep both open, but with the method above you can most definitely only open Share Monitor.