ARM has revealed some new security features designed for the Internet of Things, such as its effort to add TrustZone defenses to its microcontroller blueprints. You can find a nice overview at the Register.
TrustZone is usually found in ARM's application processor designs – your smartphone's system-on-chip, for example. It's been around since the early 2000s, though, first appearing in the ARMv6 ARM11 family well before the smartmobe boom.
It works by splitting the device into two domains: a secure domain and a non-secure domain. Typically, your bells-and-whistles operating system with its huge attack surface and vulnerabilities (cough, Android) runs in the non-secure domain, and the secure domain runs stuff that needs safeguarding: code-signing cryptography and fingerprint sensor drivers, say.