Many of the neat caching features of MCMS 2002 will be incorporated in SharePoint 2007, plus some new stuff. ASP.NET output caching will also be carried over, which is great news. If all goes well, all of this will be available to SharePoint as well a the new CMS bits.
See the Caching section on the post
Performance, Performance, Performance post.
BTW, I wonder which books they were referring to in this sentence ;-)
CMS 2002 had very elaborate caching support (writers spent a whole chapter on it in CMS books!)