They do keep Wordpress up to date in the one click installs.
Mostly the one clicks tend to be wayyyy behind current version.
In the case of phpBB, I think what happaned is there became an upgrade that there was no great way to do automatically... that is upgrade any installation without human intervention, which is how it has to happen via a one-click upgrade.
I kinda wish they would do away with most of the one clicks because they aren't up to date. If you know what your doing a d/l and install/upgrade of anything is really only like 10 clicks and a few minutes.