But normally, if you miss an intermediate plugin or theme update, the latest version will be backward compatible with previous versions.
For themes that have theme support plugins (and a growing number of themes do), you really should be sure to update all those plugins, too.
When WP updates versions, you should also update any themes and plugins that show up on the dashboard Updates admin page – often they will have updates to stay compatible with WP. And, really, you should really update every time there are any updates.
If you don’t know about it, there is a free service called Infinite WP (http://infinitewp.com/) that allows you to support a whole bunch of WP sites collectively – it will update plugins, themes, and even WP automatically (You might have to initiate the updates manually – that is what I do) from one control panel. I think JetPack is doing that now, too.