The best place to get your install version is from the Servers - CMS - Metrics. Then take that version and look it up in this post.
XI R2 will not be supported after June 30, 2011 so if you are upgrading you should go to the latest 3.1 release which is currently SP3 plus FixPacks. I believe there is an SP4 due out pretty soon as well.
jwhite9 
(BOB member since 2006-07-28)