[wp-testers] Plugins do not update

[Peak Discharge]

Running 2.7rc1 on DownTownHost.

For some reason the plugin update information is not fetched. That is, I
know that half the plugins that I have installed (active or not) have been
updated since I've installed them. In 2.6.* WP would alert me when the
update was available and automatically install it if I choose to. Now,
however, WP acts as if no updates are available and I have no idea how to
force it to check for plugin updates.

Any ideas?