You know how hard it is to keep track of each and every possible plugin version change - why not make it simple? It just requires one more plugin to be installed - and from that moment on, you will have a complete overview if the plugins you use are up to date.

OK, one thing needs to be mentioned: the plugin has to be available at www.wp-plugins-db.org - but believe me: most of them will be. From all the plugins I have installed up to this point, only ONE was not listed.

Nice!

• “WP Plugins Tracker” for WordPress:
  www.wp-plugins-db.org/wp-plugins-tracker/

[Update]
Hm, still seems to be a little buggy - it shows “Dofollow” in version 4.0 - although version 2.0 is the latest… anyway: it’s still nice.