NetBSD 6.1 is the first major update to the operating system following the NetBSD 6.0 release last October. Among the features that are coming to NetBSD 6.1 include improvements to the NetBSD Packet Filter (NPF), ARM support improvements, DTrace on AMD64 (x86_64) architectures, the MIPS port now using GDB7, new device drivers, and port-specific improvements for ARM and other architectures. Even the Amiga architecture got some love in NetBSD 6.1 RC1. The Raspberry Pi port of NetBSD is also in good shape and offers "nearly-complete support" in version 6.1.
More NetBSD 6.1 details can be found in the Release Candidate 1 announcement at NetBSD.org.