So, does the PAUSE indexer have trouble updating the module lists?

That happens from time to time. See Is 02packages.details.txt.gz outdated?, Why isn't a newer version of a module installable from cpan?

I can confirm, it appears to have happened again :/

$ cpanp l HTML::Template HTTP::DetectUserAgent
[MSG] Checking if source files are up to date
Details for 'HTML::Template'
Author                   Sam Tregar (sam@tregar.com)
Description              a simple HTML templating system
Development Stage        Mature (no rigorous definition)
Interface Style          Object oriented using blessed references and/
+or inheritance
Language Used            Perl-only, no compiler needed, should be plat
+form independent
Package                  HTML-Template-2.9.tar.gz
Public License           Standard-Perl: user may choose between GPL an
+d Artistic
Support Level            Mailing-list
Version on CPAN          2.9
Contains:                HTML::Template                               
+ 2.9

Details for 'HTTP::DetectUserAgent'
Author                   Takaaki Mizuno (cpan@takaaki.info)
Description              None given
Development Stage        Unknown
Interface Style          Unknown
Language Used            Unknown
Package                  HTTP-DetectUserAgent-0.01.tar.gz
Public License           Unknown
Support Level            Unknown
Version on CPAN          0.01
Contains:                HTTP::DetectUserAgent                        
+ 0.01
[download]

Also of interest is http://mirrors.cpan.org/ the status of CPAN mirrors

perl.org having http://log.perl.org/2011/08/network-trouble.html