firefox addons and their silly news tabs
Solution 1:
One option is to globally disable automatic updates of add-ons. This means that you can manually update add-ons - and deal with update news - at your leisure.
Clearly this has the disadvantage that your add-ons are not automatically updated. But Firefox (at least in version 4 beta 11) can be configured to automatically check for updates to add-ons (in Options > Advanced > Update), but without installing them (by deselecting Update Add-ons Automatically in the settings in Add-ons Manager).