According to my userinfo page, I have 1,004 journal entries. But syncitems is giving me 1,043 unique items.
I tested it on another account with far less entries (8) and it works fine.
I also tested it with the "test" account. The userinfo page claims 1,358 entries, while syncitems returns 1,431. (Due to a bug in my XMLRPC libs that I have yet to hunt down, I am unable to retrieve all the entry id's for the test account to ensure that they are indeed 1,431 unique items being returned.
BTW- When I say "unique" I mean that the syncitems "item" values are unique. You know, the "L-1232343" value.
One thing that does seem to be correct is that the number of items syncitems claims there are in total is equal to the number of unique items I receive.
Perhaps the userinfo page is incorrect, only updated occasionally, or is not counting private or friends-only posts?
I haven't researched the data heavily, as 1,043 items is a lot to deal with.