Hi Eric,
Don't forget the the Number One most important factor in IT Security is end user action. SEP (and Symantec Mail Security for MS Exchange, if you are using that) are excellent technical sollutions, but do continue to ensure that your mail client users are educated to follow best practices: not to click on unexpected links in emails, not to run unexpected email attachments, not to fall for scams that inform them they have won $40m in a lottery they never entered.... &: )
Here's a link to some Security Response SEP best practices: http://www.symantec.com/business/theme.jsp?themeid=stopping_malware&depthpath=0
Please do let the forum know if there is anything additional that you require!
Thanks and best regards,
Mick