This is interesting stuff, but it seems to me that the "right" way to architect such a feature following X3C recommendations, would be to produce xsl-fo either directly from the wikitext, or by transforming the XHTML version, and then produce pdf from the XSL-FO using Apache FOP, or a toolchain like passivetex.
Xsl-FO provides the ability to model page layouts and then flow data into pages. -- Rick DeNatale
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