Hi,
Let me introduce myself (as much as pertains to this letter): I am one
of the lead developers of Drupal core (Drupal, I believe, is quite
well known by now), I maintain the form API and the menu system. I do
not know much about PHP internals, but I spent most of the awake time
in the last four years writing code in PHP.
I can't wait to have lambda and closures in PHP. I am well aware of
the fact that it will be many years before we can raise the minimum
PHP version of Drupal to 5.3 but if we do not start now then it will
be even later :)
Just a real life quick example,
http://api.drupal.org/api/function/_filter_url_parse_full_links/6 has
no reason to exist, it should be lambda, it's called from
preg_replace_callback only.
So: a resounding yes.
Regards
Karoly Negyesi