Well, the bigger majority of the organisations running Microsoft Exchange are; around 70% to be precise …
Every once in a while I keep track of the sites that run user polls to see what the currect score is. The share of Microsoft Exchange 2003 over the older versions is a topic of constant speculation and a target user group for Microsft’s competition ofcourse ;-).
The latest user polls look very promising and show tremendous growth over the last year or so …
In January 2006 WindowsITPro did a user poll amongst their readers :
Search Exchange ran a poll in 2005 :
and recently in February 2006 :
What’s ofcourse most important to notice is that the Microsoft Exchange 5.5 share has reduced with 50% from 25% in 2005 to about 12 – 14 % in 2006. I don’t have other details on this, but most likely the majority of organsiation still running Exchange 5.5 are in the SME market.