I have recently been using a similar construct to turn 'links' in my XML documents (that become an HTML file) into real links. However, using $1 for both the title and the URL was not flexible enough, so (inspired by this site) i decided to use the form [URL|title] and this regex:

s/\[([^ |]+)\|([^\]]+)\]/<a href="$1">$2<\/a>/g;
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jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
F--F--F--F--F--F--F--F--
(the triplet paradiddle)