Apparently, some folks have been able to take a peak at the Alpha build for Android 4.2, and discovered some interesting things. It appears that Google may be beefing up security in the newest version of Android. Here's a quote with a brief summary of these security enhancements,
It's important to note that these features may not show up in the final build, but could be experimental for the future. Still, it's awesome to see that Google is pushing forward to make Android more secure down the line. Now, if we could just get the carriers/OEMs to update more quickly...With that in mind, first comes Security-Enhanced Linux (SELinux). The kernel add-ons makes it so that apps don’t have access to all files. You can pick from three options from SELinux: Disabled, Permissive and Enforcing. Permissive will log apps activity but won’t actually block apps root access and Enforcing does just that - blocking apps for maximum safety. This will bring almost desktop-like security options to Android, and with so many reports (true or not) about malware on the platform, it’s most definitely good news.
Secondly, the code mentions VPN lockdown. This is a change from the current model that allows data to be sent over regular connection when users sign out of a VPN network, and that won’t be possible with this new feature.
Finally, and probably most importantly, Android gets itself effectively rid of SMS scam schemes. How? Some apps work undercover sending paid text messages to select numbers without letting you know about it. You’d still have to pay hefty sums for those texts. Now, Google will simply detect whenever an app sends such a message and put out a message right away to warn you.