When your blog presents a list of plugin to update, update them one by one, never two or more at once.
Sometime plugins have incompatibilities. No coder want his plugins with problems, believe me, but sometime it happens.
Updating a single plugin helps you to discover is problems are present after that update. If you update two, three, four plugin at once, which is giving problems? Or errors come from the interference between two of them.
Coder well know that methodology (or at least they should): do one change, test it. Do another, test it.
It’s a simple rule to follow, don’t miss it!