Digging a bit deeper into R3 and will be posting some stuff. I already talked about what happens if a computer is in two collection with different power policy settings. In summary, SCCM will utilze the least impactful setting. But what if the computer is one collection that has the power management setting enabled but is set to 'never apply power management...' and in another collection that has power settings configured?
What you will see reflected in the pwrmgmt.log on the computer is an entry "This machine has been opted-out from any Power Policy changes by policy". So, because the least impactful setting is to not apply power settings, that is what the client does. If you disable the power management setting on the collection that was set to never apply, the computer is then able to get the other power policy as expected.
Also remember that the power reports will use SRS ONLY! So, this is a great time to implement SRS on your SCCM site and get familiar with it.
Also, there are some questions around if you need to install R2 before you install R3. The answer is no. You DO need to install SP2, but you can install R3 directly and it will install and enable the R2 features as part of the R3 install. Also don't forget to deploy the client hotfix and don't forget to review the MOF changes that are made so you can get an idea of what is in there.