Opalis is a unique offering within the Microsoft System Center Suite offering. With all other System Center Products once you have successfully installed and configured them, they are actively doing something. This is not the case with Opalis, once you have installed Opalis the work finally really begins. In my opinion this is the best thing about Opalis. Opalis is simply a data-bus that passes variables from one piece of code forward to other pieces of code. This means that at the end of the day it will do exactly what you tell it to do and you can make it do literally anything (if you can do it with .NET or Java, Opalis can be extended to natively do that same function). On the flip side though, there is no magic. Putting in an Opalis environment will not magically give you an automated Virtual Server Deployment process, or an automated alert resolution framework, what it does is give you the tools to build these on.
Opalis comes out of the box with a number of Integration Packs, or sets of pre-bundled code that allow you to interface with various things. Charles Joy has blogged about all of the current Integration packs Here. The wonderful part about Opalis though is that you are not limited to integrating with only the things that have a Microsoft Provided integration pack. You can create your own integration packs using .Net or Java and wrapping them with QIK. Charles also has a great set of Video blogs to get you going on writing your own Integration Packs on his YouTube Channel here (Look for the QIK series).