Who wants to plow through a bunch of security bulletins each month, many of which might not even apply to your network because you aren't running the particular operating systems or server software that's affected, to find the ones that are relevant to your organization? It takes time, and time is something that's in short supply for most busy IT pros. Microsoft just launched a new service designed to help. It's a good start - but still falls short of the functionality of third party patch management solutions.
Read my analysis of it here: