Showdown at the OK Corral?

The first thing that comes to mind when you look at Cisco's purchase of IronPort is whether or not this is, finally, going to be the beginning of a direct confrontation between Cisco and Microsoft.  Up until now, both companies have nimbly avoided the appearance of a head to head battle despite the fact that they could go into direct battle in several areas (such as NAC and NAP).  And it has probably been a wise decision on the part of each to avoid a fight -- especially since most enterprise customers consider each to be strategic and would prefer them figuring out ways to work together.  But the IronPort acquisition positions Cisco directly against Microsoft's new Exchange 2007 Edge Server, a product built specifically to fit into the DMZ and reduce/eliminate the need for third party mail cleansing products.  Cisco might argue that their products apply more broadly than to just Exchange, but the spending in the market tells a different story as Exchange spending far exceeds the sum of the other enterprise e-mail systems.  Maybe this point wasn't that obvious to Cisco when it decided to enter this sector of the business -- up until recently, Microsoft didn't have much of an e-mail hygiene story.  But in the past Exchange 2007 is barely out of the starting gate -- it's going to be fun watching to see how this showdown shapes up.