You can grab the new book online from the Microsoft Download Center. Oh, and for Pete Cole's benefit, the SDK documentation is here! [via Tim Sneath, New Features in Windows XP Service Pack 2: Again!]
Updated docs, but no bits - I'll keep asking
(Oh, and the SDK documentation link is not not a link to a nice relevant section in the SDK saying 'ah, dear reader, for your convenience and delectation, a summary of the new apis etc etc in XP SP2 is thus: ...., its just a link to the front page of the SDK on MSDN with a Whats New link that very noticably does not list what is new in IE, the definitive list still seems to be here, though that misses the changes in IOleCommandTarget).
I may be beginning to annoy people at MS, for which my apologies - just man trying to do job here.