AVG Technologies has released a Service Pack 1 upgrade for its Anti-Virus Free 2012, Anti-Virus 2012, Premium Security 2012 and Internet Security 2012 packages.

And while the update includes its share of bug fixes and minor tweaks, it also features three small but useful changes which qualify as real improvements to the package.

SP1 includes a new browser add-on, for instance, AVG Do-Not-Track, which aims to keep you safe from tracking ads. (And it is just an add-on; you don’t have to install the AVG toolbar to get it.) By default this uses the Do Not Track HTTP header to indicate that you don’t want to be tracked, and will block 37 major networks anyway if they don’t pay attention.

Check the Do-Not-Track configuration settings for some useful options

And although the new technology won’t initially block networks which you might find useful – social buttons from Facebook, Google +1, LinkedIn and Twitter, say, or Google Analytics – if you’d prefer a more thorough approach then that’s easy to change. Click the Do-Not-Track toolbar icon to view its settings, and you can disable all networks with a click, and optionally ask to be alerted when active trackers are detected on a site.

Elsewhere, the Wifi Guard introduces an additional check when your computer tries to connect to a wireless network with a name that you knew already, but in a different location. Instead of connecting automatically you’ll be asked whether you want to use that network, giving you a little extra protection against SSID spoofing.

And we’ve always found it slightly odd that AVG scanned for rootkits separately from other malware, but that’s also changed: a whole computer scan with AVG 2012 SP1 now checks for everything. If you prefer the previous approach, though, maybe for performance reasons, then that’s easily fixed. Just open the Scan Options dialog, clear “Scan for rootkits” and it’ll work as in previous editions.

Do-Not-Track is clearly the major addition here, then, but the other tweaks are also welcome. And if you’d like to sample them for yourself, then the Anti-Virus Free 2012 SP1, Anti-Virus 2012 SP1, Internet Security 2012 SP1 and Premium Security 2012 SP1 downloads are available now.