I can't count the number of times I've had to roll back client updates just in the last 6 months! having this ability would be a huge timesaver.
I agree with this one...if we can't have application installs that can perform multiple steps within the same installation then we need to use task sequences but they can be scary to our customers to use them since they appear and behave as if they're installing a new operating system. If we can have them appear as software then this fear will go away and so will our complexity!
We've just started using SCCM after coming from an Altiris world. It is actually quite a change having to figure out dependencies rather than create application installations that can have multiple steps. In Altiris there's a package and a job. We can use packages inside of jobs and the jobs can have several tasks (including logic, if necessary). We can then deploy and publish the job rather than just a package. This is extremely useful in the situations where we, like others, need to apply a license file, registry change or delete/add shortcuts. Altiris (now Symantec) has been doing this for more than 10 years and yet it doesn't exist here.