MT Wiki : Blog StatsCODE
Entries: <MTBlogEntryCount><br />
Comments: <MTBlogCommentCount><br />
What do you mean by last update? Here are two options:
Date of the latest entry:
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Latest Entry: <MTEntries lastn="1"><MTEntryDate></MTEntries>
Date the page was last rebuilt - either manually, by posting, or by a comment/ping:
CODE
Last Rebuild: <MTDate>