In the beginning, there was the Exchange server, and it was good. One box did it all, and there was no concept of roles.
Ross Smith IV, the Principal Program Manager for Office 365 Customer Experience, published an interesting post on the Exchange team blog, here are the key takeaways
In another example of business and law enforcement cooperation, the Simda Botnet was taken offline last week.
March brings Exchange admins big updates for all three of the currently supported versions. You may want to take a look at these, get them tested, and get them deployed in your next change window.
Just in case you missed it, Windows 2003 goes EOL (End of Life) on the 14th of July 2015. If you are am Exchange Admins this is why you should care!