My among branch fixes backlinks result is lossy, then uses that to provide pagestats for links from a subset of pages. From the docs included in the patch:

The optional among parameter limits counting to pages that match a PageSpec. For instance, to display a cloud of tags used on blog entries, you could use:

[[!pagestats  pages="tags/*" among="blog/posts/*"]]

or to display a cloud of tags related to Linux, you could use:

[[!pagestats  pages="tags/* and not tags/linux" among="tagged(linux)"]]

I use this on my tag pages on one site, with the following template:

[[!pagestats  pages="tags/* and !tags/<TMPL_VAR raw_tag>
    and !tags/photogallery"
  among="tagged(<TMPL_VAR raw_tag>)"]]

[[!inline  pages="tagged(<TMPL_VAR raw_tag>)"
  archive="yes" quick="yes" reverse="yes" timeformat="%x"]]


merged thanks --Joey