SCEP SP1 questions

So I already have SCCM SP1 rolled out everywhere and I have just found out there is a SCEP SP1 which we dont have installed yet.

http://blogs.technet.com/b/configmgrteam/archive/2013/04/05/announcement-microsoft-anti-malware-platform-update.aspx

Is it only available as a windows update?

are there any server side changes?

is it applicable to an SCCM sp1 managed client? the above link seems to suggest its only applicable to standalone clients

My workstations are detecting it as applicable when I run windows update however my SCCM SP1 infrastructure servers are not is that weird?

Thanks